Astronomische    Gesellschaft

Annual Fall Meeting and 82nd General Assembly

 Abstract List as of June 18, 2019 » topCOS - "Recent advances in cosmology" H. Alavirad, P. Ameri Slowly rotating black holes in Brans-Dicke-Maxwell theory (Poster)Abstract In this paper, we construct a class of (n+1)-dimensional (n ≥ 4) slowly rotating black hole solutions in Brans-Dicke-Maxwell theory with a quadratic potential. These solutions can represent black holes with inner and outer event horizons, an extreme black hole and a naked singularity and they are neither asymptotically flat nor (anti)-de Sitter. We compute the Euclidean action and use it to obtain the conserved and thermodynamics quantities such as entropy which does not obey the area law. We also compute the angular momentum and the gyromagnetic ratio for these type of black holes where the gyromagnetic ratio is modified in Brans-Dicke theory compared to the Einstein theory. » topCOS - "Recent advances in cosmology" S.W. Allen X-ray cluster Cosmology (Talk)X-ray observations of galaxy clusters provide powerful cosmological constraints via two independent methods. The first uses measurements of the baryonic mass fraction in the largest, dynamically relaxed clusters. This method, like type Ia supernovae studies, measures distance as a function of redshift and traces the acceleration of the Universe directly. It also provides a tight constraint on the mean matter density. The second method uses the observed evolution of the cluster mass function. It leads to tight constraints on the amplitude of mass fluctuations and powerful, complementary constraints on dark energy. I will present the latest results from our team's work on both experiments, employing a rigorous, self-consistent Bayesian approach that accounts for survey biases, captures fully the degeneracies between parameters and incorporates conservative allowances for systematic uncertainties. I will place the results in context with other current experiments and discuss the prospects for improvement in the near-to-mid term. » topACT - "Exoplanets, stellar activity, and the star-planet connection" M. Ammler-von Eiff, N.C. Santos, S.G. Sousa, J. Fernandes, T. Guillot, G. Israelian, M. Mayor, C. Melo A homogeneous spectroscopic analysis of host stars of transiting planets (Talk)We present a homogeneous spectroscopic determination of the properties of 13 stars harbouring transiting planets. Such work becomes increasingly important in extra-solar planet research. The iron excitation and ionization equilibria were imposed on spectra with high resolution and high signal-to-noise ratio yielding effective temperature, surface gravity and iron abundance. The new results call attention to some previous determinations of planetary radii and the iron abudance scale of the TrES and HAT objects. 11 further host stars of transiting planets have been studied before using the same methods, giving in total 24 uniformly analyzed stars which follow well the known metal-rich distribution of planet host stars. » topACT - "Exoplanets, stellar activity, and the star-planet connection" R.I. Anderson, A. Reiners, S.K. Solanki Zeeman broadening in optical spectra of F- & G-type Stars (Poster)Magnetic field detectability in solar-like stars is investigated by measuring Zeeman broadening. We perform spectral line inversion of high-quality optical CES data using SPINOR to construct χ2-maps for grids of fixed average magnetic flux densities, Bf. 3σ upper limits for the Sun and 61 Vir (G6V) are established at Bf = 250 G and Bf = 150 G, respectively. A detection of Bf = 500 G is made for 59 Vir (G0V). First direct evidence for a magnetic field in a late F-type star is found in HD 68456 (F6V) with Bf ~ 1 kG. 3σ errors on Bf range between 150 G and 450 G. Results are compared to previous measurements, where available. We conclude that Zeeman broadening remains difficult to detect, even given the present data quality and sophistication of radiative transfer treatment. » topMSC - Plenary session (posters only) E. Angelakis, J. A. Zensus The International Max Planck Research School for Astronomy and Astrophysics at the Universities of Bonn and Cologne (Poster, registered after deadline)The International Max Planck Research School for Astronomy and Astrophysics at the Universities of Bonn and Cologne. » topGAL - "Galactic archaeology" B. Anguiano, K. Freeman, M. Steinmetz, E. Wylie de Boer, and the RAVE collaboration RAVE: the Age-Metallicity-Velocity relation in the nearby disk (Talk)One of the most powerful tools for understanding the evolution of the Galaxy is the local stellar Age-Metallicity-Velocity relation (AMVR) in the nearby disk. However there are still remarkable differences in the form of this relation (e.g. Edvardsson et al. 1993, Rocha-Pinto et al. 2000, Quillen & Garnett 2000, Feltzing et al. 2001, Holmberg et al. 2007). Using a carefully selected sample of turn-off stars from the RAVE survey we are working in a new derivation of the AMVR. RAVE provides accurate kinematics and a first estimate of metallicity, temperature and gravity. Follow-up observations allow us to obtain accurate fundametal parameters in order to derive reliable ages and generate an AMVR for the nearby disk. The status of the project and preliminary results from our spectrophotometry observations will be discussed. » topACT - "Exoplanets, stellar activity, and the star-planet connection" R. Arlt The solar activity in the 18th century (Poster)Until recently, detailed information on sunspots has been available starting in 1874. The analysis of about 1000 drawings of the solar disk from 1749-1799 now allows new insights in the butterfly diagram and several other features of solar activity not covered by the mere sunspot number. A weak cycle, hidden in the very long Cycle 4, has been detected using the spot positions. Implications for the variability of the solar dynamo are discussed. » topHIS - "WG History of Astronomy" R. Arlt Sunspot observations in the second half of the 18th century (Talk)Until recently, detailed information on sunspots has been available starting in 1874. The analysis of about 1000 drawings of the solar disk by Johann Staudacher made between 1749 and 1799 now allows new insights in the butterfly diagram. These and additional drawings made at Armagh Observatory deliver new evidence for a weak cycle at the end of the 18th century, which has been buried in a long Cycle » topISM - "Dynamical processes in the interstellar medium" B. Arnold, G. Hensler The evolution of high-velocity clouds (Poster)We carried out three-dimensional simulations of high-velocity clouds (HVCs) using the adaptive-mesh code Flash. We aim at investigating the evolution of a HVC while it penetrates into the hot galactic halo of our galaxy. The processes of heating, cooling, and saturated heat conduction are considered. It was shown in previous works (Vieser & Hensler, 2007, A&A, 472, 141; Vieser & Hensler, 2007, A&A, 475, 251), that saturated heat conduction suppresses the occuring hydrodynamical instabilities and therefore the life time of the cloud is significantly extended. Hence, a necessary condition is given for prospective star formation in HVCs. Within this work we wish to figure out further processes being able to trigger Jeans instabilities in many regions of the HVC, such that a massive star burst can be initiated. » topGAL - "Galactic archaeology" M. Asplund The cosmological lithium problem (Talk)n/a » topPLE - "Plenary session" M. Asplund Precision solar/stellar spectroscopy: does the Sun have a subsolar metallicity? (Review Talk)The solar chemical composition is an important ingredient in our understanding of the formation, structure and evolution of both the Sun and our solar system. Furthermore, it is an essential reference standard against which the elemental contents of other astronomical objects are compared. In recent years the solar abundances of the most common metals - C, N, O and Ne - have undergone a quite dramatic downward revision, driven by our work on developing realistic 3D hydrodynamical solar model atmospheres, non-LTE line formation and improved atomic/molecular data. While welcomed by most areas of astronomy, these changes have caused a great deal of consternation for helioseismology. I will also discuss how the Sun compares with other solar-type stars. Surprisingly the Sun is unusual in its chemical properties, a fact that most likely is due to it hosting planets. Our findings open the enthralling prospect of being able to identify stars harbouring planets purely from their chemical compositions. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" H. Aurass, G. Rausche, S. Berkebile-Stoiser, A. Veronig Deciphering the solar flare energy release site through radio spectroscopy (Talk)During a SOHO-MDI microflare campaign we found a radio spectral line at 314± 1 MHz. Its solar origin can be confirmed for the first time by the gradual flux-over-time profile, and by the highly correlated flux profile of the 12-25 keV hard X-ray burst observed by RHESSI. With that knowledge we find the radio spectral line also in the impulsive phase of complex and strong flare events. We discuss consequences in terms of flare particle acceleration and the reconnection process. » topCOS - "Recent advances in cosmology" S. Bailey for the Nearby Supernova Factory Making Cosmology's best standard candles even better: the Nearby Supernova Factory and spectrophotometric observations of SNe Ia (Talk)The Nearby Supernova Factory is a program of integrated discovery, followup, and analysis of Type Ia supernovae (SNe Ia). We have discovered over 1000 SNe and followed 185 SNe Ia with spectrophotometric observations with a median of 14 spectra per SN starting as early as two weeks before peak brightness. In this talk I will give an overview of the project and present our intial results which show how spectrophotometric observations of SNe Ia can measure luminosity distances with greater accuracy than traditional methods based upon corrections for light curve shape and color. These new methods increase the statistical power per SN, constrain systematic errors from different SN Ia subtypes and their population evolution with redshift, and give insights into the underlying physics of the explosions. I will also show how these observations compliment high redshift SN Ia datasets, allowing them to be combined with minimal inter-calibration uncertainties, thus addressing one of the dominant systematic errors facing current cosmology analyses. » topCOS - "Recent advances in cosmology" A. Balaguera-Antolinez, A.G. Sanchez, H. Böhringer, C.Collins, L. Guzzo REFLEX 2 Galaxy Cluster survey: the power spectrum (Poster)We present preliminary results of an ongoing analysis of the power spectrum measured from the new ROSAT-ESO Flux-Limited X-Ray (REFLEX) II galaxy cluster catalogue sample. The data shows an increase in the amplitude of the power spectrum with increasing X-Ray luminosity. Our results show good agreement with the mean power spectrum obtained from an ensemble of mock galaxy cluster catalogues built from a suit of large volume LCDM N-Body simulations (L-BASSIC II). This new measurement can be used in combination with other datasets to place constrains on the values of the basic cosmological parameters. » topPLE - "Plenary session" R. Banerjee From molecular clouds to massive stars: star formation in numerical simulations (Highlight Talk)Galactic star formation proceeds through a complex interplay between various physical and chemical processes. This complexity and the intrinsic non-linear interaction of gravity makes it almost inevitable to tackle this problem with three dimensional numerical calculations. In this talk, I will show our latest progress in studying present day star formation based on numerical simulations. Present day star formation takes place in molecular clouds (MCs) and giant molecular cloud complexes (GMCs). But how do these cold molecular clouds condense out of the warm atomic interstellar medium? Here, I will present our model of MC formation in the magnetised interstellar medium (ISM) by colliding streams. In this model, triggered thermal instabilities result in condensates of turbulent, self-gravitating, molecular clumps which eventually collapse to form stars. The global contraction of the molecular cloud leads to the environment in which massive stars will form. These stars are typically born in clusters, as we also could show in our novel simulations of massive star forming regions. Furthermore, the ionisation feedback from these stars produce H ii regions which are highly dynamic and take all kind of shapes during their lifetime, in agreement with observations. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" M. Bárta, J. Büchner, M. Karlický Total volume of non-ideal regions in cascading magnetic reconnection and particle acceleration in solar flares (Talk)The \lq canonical\rq solar flare model sketched frequently in textbooks and papers as a X-point type reconnection below erupting filament is challenged by the huge number of energetic electrons as it is inferred from HXR flare observations because of the relatively small volume where particles can be accelerated. Therefore, the \lq chaotic current-sheet\rq class of flare models based (e.g.) on braiding of magnetic flux-tubes whose footpoints are advected by turbulent photospheric motions has been developed. These models provide sufficient acceleration volumes but, at the same time, they lack natural explanation of large-scale organisation observed in solar flares (e.g. loop arcades). In the presented contribution we investigate the possibility that so called cascading reconnection suggested by Shibata and Tanuma (2001) as a concept overcoming the scale gap between the global CS width and dissipative region size is capable to reconcile the canonical model with observed flux of energetic electrons as well. We analyse the results of our AMR (Adaptive Mesh Refinement) MHD numerical simulations of reconnection in vertical coronal CS in order to find scaling laws for sizes and peak electric field of non-ideal (dissipative) regions. Based on the obtained spectra we estimate the total volume of dissipative regions, average DC electric field in them and we try to roughly infer the flux of accelerated electrons. » topGAL - "Galactic archaeology" A. Barzdis, L. Zacs High resolution spectroscopy of two metal-poor red giants: HD 232078 and HD 218732 (Poster)High resolution (R = 67 000) optical spectra of two metal-poor ([Fe/H] ~ -1.5) red giants, HD 232078 and HD 218732 were obtained with the FIES spectrograph at the 2.56 m Nordic Optical Telescope. Both target stars are chromospherically active, variable red giant stars showing emission in the wings of Hα absorption line, and radial velocity variations. According to the radial velocity measurements HD 218732 could be in a binary system with a period of 567 days, although the cause of the radial velocity jitter for HD 232078 is still not confirmed. Here we present the results of LTE abundance analysis for 24 chemical elements, and highlight specific spectral features of these stars. » topPLE - "Plenary session" H. Baumgardt Hyper-velocity stars in the galactic halo (Highlight Talk)The formation of hyper-velocity stars (HVS) is a natural consequence of the presence of massive black holes in dense stellar environments like the Galactic center and Hills (1988) was the first to point out that the tidal disruption of stellar binaries in the field of a massive black hole can produce hyper-velocity stars. HVS move with velocities up to several 1000 km/sec and are unbound to the potential of the Milky Way. They are different from classical runaway stars which cannot reach velocities of more than a few hundred km/sec. The first HVS was discovered in 2005 and photometric and spectroscopic surveys have since then revealed a whole population of these stars in the Galactic halo. During my talk I will present different formation scenarios of HVS, and explain their relation to observed populations of young stars in the galactic centre and how observed properties of HVS can constrain their formation scenario. I will also show how precise proper-motion measurements of hyper-velocity stars can be used to probe the shape of the Galactic halo and the nature of dark matter. » topISM - "Dynamical processes in the interstellar medium" V. Baumgartner, D. Breitschwerdt Modeling the evolution of superbubbles in disk galaxies (Talk)Winds of massive stars and subsequent supernova explosions create large cavities in the interstellar medium (ISM), which are surrounded by cold dense shells, consisting of the hot, high-metallicity gas ejected by the stars, and swept-up ISM. These superbubbles can accelerate along the negative gradient of a density stratified disk. As a result, the shell will break-up and metal-enriched material is ejected into the halo, or even to the surrounding intergalactic medium. We present a 2D analytical model that describes the expansion of a superbubble in space and time. It is based on the calculations of Kompaneets (1960) for shock wave propagation due to a strong explosion in an exponentially stratified medium. Our primary modification is to include a time-dependent energy input rate due to subsequent supernovae, instead of a single explosion by using an initial mass function and the main-sequence lifetime of the SN-progenitors. We can find out when a bubble starts to accelerate into the halo and how much energy is needed for blow-out depending on the scale height and density of the ISM. The timescale for the occurrence of Rayleigh-Taylor instabilities in the shell is also calculated. By comparison of our model to observed bubble structures in the Milky Way, we are able to determine their evolutionary status and derive properties of the local ISM. » topISM - "Dynamical processes in the interstellar medium" V. Baumgartner, D. Breitschwerdt Ram pressure stripping of galactic halos in star forming cluster galaxies (Poster)The intracluster medium (ICM) in galaxy clusters contains heavy elements with about 1/3-1/2 of the solar abundance. These heavy elements (metals) are the products of stellar nucleosynthesis and are most likely expelled by galactic winds or lost from the galaxies due to interactions with the intracluster gas. We investigate the stripping of hot galactic, high-metallicity halos, which occurs as galaxies are moving through a cluster, being subject to the ram pressure of the ICM. The aim of our work is to modify the criterion of ram pressure stripping for galactic disks (Gunn & Gott 1972), including the internal structure of galactic halos, as derived from their dynamics in the interstellar medium and subsequent break-out into the halo. Moreover, the amount of metals present in the halos must be known in detail in order to estimate the contribution of halo stripping to the metal enrichment of the ICM. » topACT - "Exoplanets, stellar activity, and the star-planet connection" J. Bean The CRIRES search for planets around the lowest-mass stars (Talk)We are currently carrying out a search for planets around the lowest-mass stars using the CRIRES instrument at the VLT under the auspices of an ESO Large Programme. The main purposes of this work are to illuminate the correlation between stellar mass and planet formation, improve the census of planets, and identify new planets that can be followed-up for detailed study. We have developed and are utilizing a new type of gas cell for obtaining high-precision radial velocities of late-type stars in the nIR spectral region. Observations in the nIR offer the advantages in that the targetted stars are bright enough for high-precision spectroscopy, and potential the noise contribution from stellar activity is significantly reduced. In this talk I will present preliminary results from the project, and in particular the work to obtain radial velocity precisions better than 10 m/s for stars at the bottom of the main sequence for the first time. » topCOS - "Recent advances in cosmology" G. Becker A status report on the intergalactic medium and cosmic reionization (Talk)The intergalactic medium offers the most direct insight into two major transitions in the early Universe: the cosmic reionization of hydrogen at z > 6, and the later reionization of helium. I will review recent advances in IGM studies, focusing on new observational and theoretical work on reionization. The CMB, the evolution of the Ly-α forest, high-redshift metal absorption lines, temperature measurements, and deep galaxy surveys are slowly producing a clearer picture of the IGM at the highest observable redshifts. At the same time, simulations of reionization are producing more sophisticated insights into the relevant physics. Many mysteries remain, however, and these will be addressed with a variety of new experiments, including observations of the redshifted 21 cm line with facilities like LOFAR and MWA, and of the He ii Ly-α forest with HST/COS. » topMSC - Plenary session (posters only) T. Beitz, O. Reich, H.-G. Löhmannsröben Radiation transport and ion-molecule reactions studied by Photon Density Wave (PDW) spectroscopy and Ion Mobility (IM) spectrometry (Poster)Detailed knowledge of radiation transport and ion-molecule reactions are of crucial importance for the understanding of astrochemical processes. Results of our laboratory studies on PDW spectroscopy and IM spectrometry are presented. It is shown that PDW spectroscopy with high-frequency modulated diode lasers provides unique possibilities for the characterization of highly turbid media, whereas laser-based IM spectrometry is a suitable experimental tool for the investigation of the formation of large anionic PAH clusters and PAH-mediated ion-molecule reactions. Strategies will be outlined to adopt both experimental techniques to astrochemical conditions. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" N. Bello González, H. Balthasar, F. Kneer Magnetism and dynamics of the NOAA 10988 sunspot fine-structure (Talk)On April 1, 2008, one of the last biggest sunspots of cycle 23, NOAA 10988, was observed with the Göttingen Fabry-P\'erot spectropolarimeter attached to the German Vacuum Tower Telescope (VTT, Observatorio del Teide, Tenerife). Two-dimensional maps of the full Stokes vector were obtained scanning along the Fe i 6173 Å (g = 2.5) and Fe i 5576 Å (g = 0) spectral lines within ~  160 s (compared to about one hour scanning with a grating spectrograph). The spectral scanning steps are 17.7 mÅ and 16 mÅ, respectively. A spatial resolution of ~ 0''.4 is achieved after applying speckle reconstruction techniques. The magnetic field vector and line-of-sight velocities derived using the Stokes Inversion based on Response functions (SIR) code allow us to study in detail the magnetism and dynamics of the fine-structure of penumbrae, light bridges and umbral dots present in the NOAA 10988 sunspot. » topPLE - "Plenary session" S. Berdyugina Molecular spectroscopy of the Sun and stars (Highlight Talk)Molecules are found in a large variety of astronomical objects, ranging from clouds in the interstellar medium and comets to stars and planets and further to galaxies at high redshifts. For these objects molecular spectroscopy provides a unique tool to study their physical properties and chemical composition. Recently we started to explore the possibility to study magnetic fields of such objects with the help of molecular spectropolarimetry. Our first successful spectral synthesis of the Zeeman-split molecular Stokes profiles observed in sunspots paved the way for numerous applications in solar and stellar physics. In this talk I will give an overview of the theoretical and observational advances in molecular spectropolarimetry, including the development of the theory of the molecular Paschen-Back and Hanle effects, novel molecular diagnostics of magnetic fields in sunspots and starspots, as well as results of modeling of molecular magnetic dichroism in red, brown and white dwarfs. » topGAL - "Galactic archaeology" C. Boeche, A. Siebert, M. Steinmetz Chemical gradients in the Milky Way from the RAVE chemical abundances catalogue (Talk)The RAVE project is a large spectroscopic survey which aims at observing up to 1 million stars of the Milky Way in order to measure radial velocities, stellar parameters and chemical abundances (Steinmetz et al. 2006, AJ 132, 1645, Zwitter et al. 2008, AJ 136, 421). RAVE spectra cover the wavelength region betweee 8410 and 8795 Å with spectral resolution of R ~ 7500. RAVE is the largest spectroscopic survey before the upcoming Gaia mission, and it shares very similar characteristics. We present the RAVE chemical catalogue which holds chemical abundances for up to 12 elements of ~ 88 000 RAVE stars (more to come). This is currently the richest source of information for chemo-kinematic investigations of the Milky Way. Thanks to the proper motions (available from different sources) and distance estimations by Breddels et al. (2009, A&A submitted) we obtained absolute velocities of the stars and computed their galactic orbits for all stars in the chemical catalogue. We focused our first investigation to the present structure of the Galaxy, searching for trace of its chemical evolution by measuring the chemical gradients along the galactic radius. By using a sample of 3549 dwarf stars we measured the chemical gradients for 6 elements (Mg, Al, Si, Ca, Ti, Fe). We found that stars with low vertical velocities |W| (which stay close to the galactic plane) show an Iron gradient in agreement with previous works whereas stars with larger |W|, which are able to reach larger altitudes (Zmax) above the galactic plane, show progressively flatter gradients as function of |Zmax|. The gradients of the other elements follow this trend. In particular, stars with higher |W| could be kinematically classified as thick disk stars but they exhibit a chemical composition typical of the thin disk. The picture coming from the RAVE data does not easily fit the Milky Way formation scenario commonly accepted today. We suggest the possibility that these transition stars' having thick disk kinematic and thin disk chemical composition (already detected by other authors) might be an evolutionary connection between the thin and thick disk of the Milky Way. » topPLE - "Plenary session" R.van Boekel, M. Fang, W. Wang, A. Carmona, A. Sicilia-Aguilar, T. Henning Star and protoplanetary disk properties in Orion's suburbs (Highlight Talk)Knowledge of the evolution of circumstellar accretion disks is pivotal to our understanding of star and planet formation, yet dispite numerous theoretical and observational studies it is still poorly understood. The imaging surveys conducted with the Spitzer Space Telescope have, for the first time, allowed to assess the evolutionary state of many hundreds of disks surrounding young stars in a multitude of star forming regions. In order to interpret these data, we need reliable estimates of the stellar parameters (mass, age) and accretion properties of the individual young stars. We have conducted a large spectroscopic survey of the Lynds 1630N and 1641 star forming clouds in Orion, using VLT/VIMOS. Our medium resolution (R ~ 2500) spectra were used to spectrally classify ~ 540 stars, of which 399 were confirmed to be young stars. We used several optical emission lines to estimate accretion rates, and found that in the sub-solar mass regime it scales differently with stellar mass than previously thought: roughly as the 3rd power of the stellar mass. At approximately 1 solar mass and higher we find the same 2nd power dependence that has been reported earlier. Besides a large number of "Classical T-Tauri Stars" with still full-blown disks and mostly diskless "Weak-line T-Tauri Stars", we identify 20 new "transition disk systems" with partially dissipated disks. We show that while active accretion is less frequent around transition disk systems, those systems that are acreting do so at the same median rate as the classical T-Tauri stars. » topINS - "Innovations in spectroscopy" A. Böhm Disk galaxy evolution since z = 1 (Talk)We have constructed a data set of ~ 200 disk galaxies at redshifts 0.1 50 Msun) can enter an extremely instable phase during their lifetime which is known as the so called Luminous Blue Variable (LBV) phase. So far it is still unknown under which circumstances massive stars become LBVs, what triggers the instabilities, and whether all massive stars in a certain mass range evolve into LBVs or not. Since massive stars are built much more seldom than low mass stars and furthermore evolve much faster, they are very rare. In order to figure out general properties of these massive stars like e.g. their stellar evolution it is first of all necessary to find a sufficient number of these stars. Using photometric studies we selected a comprehensive sample of candidate LBVs and related objects in M 33. Subsequent spectroscopic investigations were made to determine the evolutionary status of our candidates. The results of these analysis are presented here exemplarily. » topACT - "Exoplanets, stellar activity, and the star-planet connection" J. Cabrera and the CEST team Additional science with CoRoT light-curves of planetary hosting stars (Talk)The CoRoT satellite was launched on December 2006 with two goals: to search for extrasolar planets and study the interior structure of stars. So far, six planets and a brown dwarf (with 20 Jupiter masses) have been reported and several results on stellar seismology are published. This presentation focus on the planetary science raised by a careful study of the CoRoT light curves: the thermal structure of the planet through the analysis of the secondary eclipse, the search for other planets in the system through the perturbations in the ephemeris of transiting planets, the search for reflected light of non transiting planets, the study of the stellar activity of the star, the interactions between the star and the planet and the search for moons and rings around transiting planets. » topINS - "Innovations in spectroscopy" L.M. Cairos, N. Caon, A. Kelz, M. Roth, P. Weilbacher Mapping Blue Compact Dwarf Galaxies with VIRUS-P (Poster)In spite of the great effort that has been done during the last two decades on the investigations on Blue Compact Dwarf Galaxies, we are still far from understand fundamental issues as the mechanism responsible for the ignition of the actual starburst, the evolutionary status of these galaxies or their star forming histories. Integral Field Spectroscopy is the ideal observational technique to explore such issues: each single exposure contains both spatial and spectral information in a large area of the galaxy, so just in one shot we collect information for all the SF regions as well as for the low surface brightness stellar component of the galaxies. Besides, the kinematical information also allow us to investigate what mechanisms ignite the star-formation in BCDs. Here we present first results on an Integral-field mapping of several Luminous Blue Compact Dwarf galaxies by using the VIRUS-P spectrograph, currently working at the 2.7 m telescope at the McDonald Observatory. » topINS - "Innovations in spectroscopy" L.M. Cairos, N. Caon, M. Roth, P. Weilbacher, A. Kelz The star-forming dwarf galaxy population in the Local Universe and beyond: the first 3D spectroscopic study of a large sample of Blue Compact Dwarf galaxies (Talk)We are carrying out a comprehensive analysis of a large sample of Blue Compact Dwarf (BCD) galaxies by means of Integral Field Spectroscopy. This dataset allow us to gain insights into the most crucial unanswered questions in BCDs research. We propose to effectively disentangle their young and old stellar populations, assess ages and metallicities of each star-forming knot, investigate the evolutionary status of the galaxy and study the kinematics of the gas and the stars. The results from this analysis will form an essential reference to understand and interpret high-z star-forming galaxies. In this talk I will report on the sample and observations and will show results for several selected objects. » topISM - "Dynamical processes in the interstellar medium" M.V. Cardaci, M. Santos-Lleó, Y. Krongold, G.F. Hägele, A.I. Díaz, P. Rodríguez-Pascual An XMM-Newton view of the narrow line Seyfert 1 galaxy UGC 11763 (Talk)We present a detailed analysis of all data taken by the XMM-Newton satellite of UGC 11763 to characterize the different components that are emitting and absorbing radiation in the vicinity of the active nucleus. The continuum emission was studied through the EPIC spectra taking profit of the spectral range of these cameras. The high resolution RGS spectra were analyzed in order to characterize the absorbing features and the emission line features that arise in the spectra of this source. A power law with a photon index Γ = 1.72+0.03-0.01 accounts for the continuum emission of this source in the hard X-rays from 10 down to 1 keV. At lower energies, a black body model with k T = 0.100± 0.003 keV provides a good description of the observed soft excess. The absorption signatures in the spectra of UGC 11763 are consistent with the presence of a two phase ionized material (log U = 1.65+0.07-0.08; 2.60± 0.009 and log N H = 21.2± 0.2; 21.51± 0.01 cm-2, respectively) in the line of sight. The physical conditions found are consistent with the two phases being in pressure equilibrium. The low ionization component is more ionized than typically found for warm absorbers in other Seyfert 1 galaxies. There are also signatures of some emission lines: O vii-Heα(r), O vii-Heα(f), a blend of the Ne ix-Heα triplet and Fe xviii at λ 17.5 Å. » topACT - "Exoplanets, stellar activity, and the star-planet connection" T.A. Carroll, K.G. Strassmeier Simultaneous detection and characterization of exoplanets and the magnetic activity of their host stars using a Doppler-Imaging approach (Poster)We present an inversion approach for the detection of extrasolar planet transits. This technique uses spectral line profile modeling and the inversion of phase dependent line profile distortions during the exoplanet transit. Similar to the Rositter-McLaughlin Effect it allows to infer a number of planetary parameters. The additional benefit of this approach is the simultaneous characterization of the magnetic activity of the host star which provides more reliable detections of possible planet transits in active systems. We will present a number of synthetic model calculation and also introduce our new principal component deconvolution (PCD) technique which allows to boost the signal-to-noise ratio of individual spectral line profiles by up to a factor of 30. » topGAL - "Galactic archaeology" N. Christlieb, M.S. Bessell, J.E. Norris Deciphering the chemical abundances of extremely metal-poor stars (Talk)I will review recent determinations, by means of high-resolution spectroscopy, of the abundance ratio trends of extremely metal-poor halo stars, as well as their individual abundance patterns. These stars enable us to study the earliest phases of chemical evolution of the Galaxy, and they provide us with indirect information about the properties (e.g., mass, rotation) of the first generation of stars in the Universe. I will also report on the discovery of the giant HE 1506-0113, which is among the 5 most metal-poor stars currently known ([Fe/H] ~ -4.0). I will present a determination of its abundance pattern, based on high-resolution VLT/UVES spectra, and discuss consequences for star formation processes in metal-poor environments, the nature of the objects that have pre-enriched the most metal-poor stars, and the efficiency of mixing processes of the ISM in the early Galaxy. » topMSC - Plenary session (posters only) M. Cisternas, K. Jahnke, and the COSMOS collaboration Quasars do not live in merging systems: no enhanced merger rate over non-quasars at log(M*/Msun)<11.7 (Poster, registered after deadline)We are trying to solve the age-old question: what is the relevance of mergers and interactions as triggering mechanisms for AGN activity? Visually, we compare the morphologies of a set of AGN host galaxies with a matched sample of inactive galaxies, both from the COSMOS survey using its high resolution imaging from HST. Specifically, we are looking for strong interaction signatures and ongoing mergers in order to determine and compare the merging fraction for both samples. We make this analysis strongly consistent by treating both samples in the same way, by making them indistinguishable between each other. We find no enhanced merger rate for AGN hosts over inactive galaxies, up to log(M*/Msun) = 11.7. We do not rule out that major mergers are one triggering factor for quasar activity, just suggest that it is either not the most significant one or that the time-lag between merging and AGN ignition is substantial. » topACT - "Exoplanets, stellar activity, and the star-planet connection" Sz. Csizmadia and the CEST Team Uniqueness of the light curve models of CoRoT planets (Poster)The CoRoT satellite was launched on December 2006 with two goals: to search for extrasolar planets and study the interior structure of stars. So far, six planets and a brown dwarf (with 20 Jupiter masses) have been reported and several results on stellar seismology are published. To find the elements of a transiting exoplanet (semi-major axis, planet-to-stellar radius ratio, inclination, etc.) from its transit light curve means the search for the minimum of a highly non-linear, multivariate function in an N-dimensional hyperspace. By numerical experiments it can be shown that more than one such minimum usually exist - depending on the noise level. In this talk the results of such numerical experiments are presented and the consequences on the planet parameters (mass, radius, average density) are discussed. The detailed modelling results of the CoRoT planets are reported. » topCOS - "Recent advances in cosmology" A. Dall'Aglio, L. Wisotzki, G. Worseck The high redshift evolution of the cosmic UV background photoionisation rate (Talk)We present a new determination of the hydrogen photoionisation rate due to the metagalactic UV radiation field, between redshifts z ~ 2 and z ~ 5. We have developed a novel and unbiased method to estimate this quantity, exploiting the distribution properties of the strength of the Proximity Effect in samples of high-quality quasar absorption line spectra. Our new method overcomes the systematic bias towards too high values of the UVB, inherent in the standard analysis technique of the proximity effect. We have applied our method to a sample of 40 high S/N, high-resolution quasar spectra taken with the ESO-VLT, finding that there is at best marginal evidence for a decrease of the UVB intensity between z ~ 2 and z ~ 4 (published in Dall'Aglio et al. 2008, A&A 491, 465). With the same method we now have analysed a sample of 2000 quasar spectra from the SDSS, extending our redshift range up almost z ~ 5 and greatly improving the statistical sampling rate. With this dataset we can estimate the UVB photoionisation rate independently for several redshift bins. We find that the UVB remains approximately constant up to the highest redshifts covered. Comparing our results with synthesis models of the UVB from the population properties of possible UV sources, we conclude that quasars do not contribute significantly to the UVB at and above a redshift of z ~ 3. Our measurements are in excellent agreement with UV light from star-forming galaxies dominating the UVB around z ~ 3-3.5, but current surveys appear to fall short of uncovering the required UV emissivity to account for a flat UVB at z > ~ 4. » topCOS - "Recent advances in cosmology" A. Del Popolo, P. Kroupa Cusp or core (Talk)We study the cusp/core problem using a secondary infall model (SIM) that takes into account the effect of ordered and random angular momentum, dynamical friction and baryons adiabatic contraction. Our analysis suggest that angular momentum and dynamical friction are able, on galactic scales, to overcome the competing effect of adiabatic contraction eliminating the cusp. The rotation curves of four LSB galaxies from Gentile et al. (2004) are compared to the rotation curves obtained by the model in the present paper obtaining a good fit to the observational data. On cluster scales we observe a similar evolution of the dark matter density profile but in this case the density profile slope flattens to α ~ eq 0.6 for a cluster of ~ eq 1014 Msun. The total mass profile, differently from that of dark matter, shows a central cusp well fitted by a NFW model. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" M.L. Demidov, H. Balthasar Stokes-metric investigations of the quiet Sun's weak magnetic field in many spectral lines (Talk)Weak magnetic fields cover most of the solar surface outside active regions and contain the dominant fraction of solar magnetic flux. Therefore, investigations of them are extremely important for solar-, geo-, and astrophysics. But reliable diagnostics of such fields are difficult due to small filling factors and low field strengths. Only joint observations in many spectral lines with different atomic properties deliver a proper information. Here we present results of full-disk high-precision Stokes-meter observations of solar magnetic fields with different spatial resolution in many diagnostically instructive spectral lines. These lines are found in the vicinity of Fe i 523.3 nm, Fe i  525.0 nm, Fe i 532.4 nm and Fe i 630.2 nm. Distributions of the magnetic field strength ratios across the solar disk in different combinations of spectral lines are explored in detail. Results of the Stokes Inversion based on Response functions (SIR) will be shown. Special attention is given to the study of magnetic field measurements in the lines Fe i 523.3 nm and Fe i  525.0 nm, because the important calibration issue of the SOHO/MDI magnetograms is based on them. According to our data, the center-to-limb variation of the ratio R = B(523.3)/B(525.0) is described by the formula: R = 1.74-2.43μ+3.43μ2, where μ is the cosine of the center-to-limb angle. » topESC - "eScience: new tools for research in astronomy" M. Demleitner, F. Freistetter Implementing VO standards: the GAVO Data Center (Talk)The Virtual Observatory (VO) is, in effect, a set of servers and client programs held together by common protocols and data representations. These are defined by the International Virtual Observatory Alliance IVOA. To be part of the VO, a data center has to support these protocols, from registry interfaces to the Table Access Protocol, and to conform to the data representations, from units to space-time coordinates. In this talk we will discuss the support of the various standards in the GAVO data center as well as implementation considerations. We place special emphasis on the impact IVOA's work on the data providers and users of the VO. » topINS - "Innovations in spectroscopy" C. Denker, H. Balthasar, A. Hofmann, N. Bello González, F. Kneer The GREGOR Fabry-P\'erot Interferometer (GFPI) - a two-dimensional spectropolarimeter for high-resolution studies of the Sun (Talk)Two-dimensional spectropolarimetry using Fabry-P\'erot interferometer has become a standard technique for high-resolution observations of solar fine-structures. GFPI will become one of the first-light instruments of GREGOR, a 1.5-meter aperture telescope currently being built at Observatorio del Teide (ODT), Izaña, Tenerife, Spain. We will discuss the GFPI optical design and strategies to accurately measure polarized light, i.e., the full Stokes vector, with high temporal, spectral and spatial resolution. To fully exploit the capabilities of the 1.5-meter aperture GREGOR, post-facto image correction (speckle masking imaging and speckle deconvolution) has to be used besides an initial correction by adaptive optics. Thus, we can enhance the data quality and approach the diffraction-limited resolution of the telescope. Recent observing runs carried out with GFPI, while still being installed at the Vacuum Tower Telescope at ODT, will be presented to illustrate the science capabilities of the instrument. » topACT - "Exoplanets, stellar activity, and the star-planet connection" I. Di Varano, K.G. Strassmeier, T. Granzer, M. Woche, D. Fügner, I. Ribas Recent developments of ICE-T (Poster)In this poster we present the status of the Ice-T project (International Concordia Explorer Telescope). Simulations of transit light curves have been carried out after having selected the optimal star fields and convolved with the expected instrumental characteristics. For the brightest stars, we showed that ICE-T should be capable of detecting a 2-R_Earth super Earth around a G2 solar-type star, as well as an Earth around an M 0 star - if these targets were as abundant as hot Jupiters. Simultaneously, the telescope can monitor the host star's surface activity in an astrophysically interpretable way. ICE-T is a double Schmidt robotic telescope, 60 cm aperture f/1.1, equipped with a wide field photometer, which will operate during the winter campaign at Dome C. Among the excellent atmospheric qualities of the Antarctic Plateau, the very low scintillation noise permits to reach high photometric precision from 0.1 to 100 mmag in the range between 9th and 18th magnitude. With a 10.3k×10.3k thinned, back-illuminated CCD it will be possible, during the long austral night, to monitor a single FOV of 65 square degrees, including more than 600,000 stars. Primary science cases are extra-solar planets and stellar magnetic activity. » topCOS - "Recent advances in cosmology" J.M. Diego, B. Partridge Sunyaev Zel'dovich effect in WMAP (Talk)We revisit the topic of measuring the SZE in WMAP data. Using the five year data and a new approach we detect a strong 10 sigma signal due to galaxy clusters. We compare the observations with theoretical models and extract some conclusions. » topPLE - "Plenary session" D. Dravins High-fidelity spectroscopy at the highest resolutions (Highlight Talk)To realize high-fidelity spectra requires great photon fluxes from large telescopes with matching high-resolution spectrometers. However, precise measurements of line profiles and wavelength positions still encounter various physical, observational, and instrumental limits. For example, although hydrodynamic simulations of stellar atmospheres may accurately predict shapes and shifts of various lines, any confrontation with observations becomes unfeasible if real spectra are limited by astrophysical and telluric blends, lack of suitable lines, imprecise laboratory wavelengths, or instrumental imperfections. To some extent, such limits can be pushed by forming averages over many similar spectral lines (averaging small random blends and wavelength errors). In situations where theoretical predictions of lineshapes and shifts can be accurately made (e.g., solar-type stars), the consistency between noisy observations and theoretical predictions may be verified; however this is not feasible for, e.g., the complex of intergalactic metal lines in spectra of distant quasars, where the primary data must come from observations. To more fully resolve lineshapes and interpret wavelength shifts, spectral resolutions on order R = 300,000 or more are required; a level that is becoming (but is not yet) available. A grand challenge remains to design efficient spectrometers with resolutions approaching R = 1,000,000 for the forthcoming generation of extremely large telescopes. » topACT - "Exoplanets, stellar activity, and the star-planet connection" S. Dreizler Transiting planets - an overview (Talk)The detection of transiting planets have boosted our knowledge about extrasolar planets significantly. During recent years, ground and space based transit surveys provided about 60 transiting planets, many of them orbiting bright stars. This enables additional observations allowing to constrain the structure and evolution for a large number of planets. An overview of recent results will given in this talk. » topISM - "Dynamical processes in the interstellar medium" C. Dreyer, M. Hegmann, E. Sedlmayr Nonlinear dynamics of expanding LPV envelopes (Talk)In the late stage of their evolution on the asymptotic giant branch (AGB) intermediate and low mass stars show a considerable mass loss caused by slow, massive stellar winds enriching the interstellar medium (ISM) with processed material. Due to the high density and low temperature prevailing in these winds, dust and complex molecules can be formed. The interplay between the dust formation and the stellar radiation field strongly influences the stellar wind and can even lead to a self-sustained oscillation of the circumstellar shell (exterior κ-mechanism). In view of the theory of dynamical systems, these circumstellar dust shells (CDS) can be considered as nonlinear multi-oscillatory systems, whose eigenfrequencies and normal modes are controlled by the intrinsic time scales of various coupled physical and chemical processes. In this context, we closely examine these eigenspectra and study the response of the shell on an external excitation by an underlying stellar pulsation of a central Long-Period Variable star (LPV). » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" F. Effenberger, S. Barra, K. Scherer, H. Fichtner The cosmic ray distribution for anisotropic diffusion in our Galaxy (Talk)The topic of Interstellar-Terrestrial Relations' has become an emerging field of interest in the last years. The long term variation of the cosmic ray flux and its implications for the climate on Earth is one major issue in this discussion. In this talk we would like to address our contribution to the latter by presenting the first results of our research in this area. In particular, we incorporate models of anisotropic diffusion in the numerical solution to the well-known Parker transport-equation. This approach has already been successfully applied to various heliophysical problems and we are now transferring our knowledge to galactic scale. Important inputs to the physical model are various recent results from observational astronomy on galactic magnetic field structure, galactic winds, cosmic ray sources and diffusion parameters. » topACT - "Exoplanets, stellar activity, and the star-planet connection" S. Eggl, E. Pilat-Lohinger, Ch. Theis The rocky road towards describing late stage planetary evolution in binaries (Poster)Discoveries of extrasolar planets in double star systems (e.g. Gamma Cephei, HD 41004, Gliese 86) have shifted questions of planetary formation and evolution within binaries into the limelight of scientific interest. Our research is focused on the late stage development of such configurations with special emphasis on Gamma Cephei. We are developing computationally feasible methods to study the systems's long term behavior influenced by remnants of the circumstellar disk. As a model for our numerical investigations, we use the full three body problem including additional drag forces to represent the disk's influence. In order to study the system's stability evolution we apply chaos indicators as well as methods based on the analysis of orbital elements. » topGAL - "Galactic archaeology" P. Eigenthaler, W.W. Zeilinger The search for fossil groups of galaxies (Talk)Poor groups of galaxies are known to be the sites where galaxy-galaxy interactions or even the coalescence of individual galaxies, galaxy merging, take place. Numerical simulations have shown that merging can proceed as long as a single, massive elliptical galaxy surrounded by an extended, diffuse X-ray halo and a faint galaxy population, a so-called fossil group remain as final product. Complementary to previous work we have queried the SDSS database via Structured Query Language (SQL) for new fossil structures. Mid-resolution spectroscopy with ISIS has been carried out at the William Herschel Telescope (WHT) to study the stellar population of fossil group central ellipticals supposed to contain the merger history of the whole group. In addition, VIMOS multi-object spectroscopy is currently carried out at the VLT to study the groups' faint galaxy populations, especially the shape of the optical luminosity function. » topESC - "eScience: new tools for research in astronomy" H. Enke Virtual Data Center (Talk)New hardware architectures and management concepts for making astronomical data in the Petabyte range available to the astronomical community are developed. An approach to some of the problems and solutions in the frame of the Virtual Data Center will be discussed. » topCOS - "Recent advances in cosmology" S. Ettori, F. Gastaldello, S. Molendi, et al. Cosmological constraints from estimates of the gas mass, total mass and concentration parameter in X-ray luminous galaxy clusters (Talk)We study the total and gas mass profiles of a sample of 44 X-ray luminous galaxy clusters observed with XMM-Newton in the redshift range 0.1-0.3 aiming at constraining the cosmological parameters σ8 and Ω_m through the analysis of the distribution of the estimates of the concentration parameter c200 and the total mass M200 in the mass range 1014-1015.4 Msun. We note that this is the statistically largest sample for which this study has been carried on between z = 0.1 and z = 0.3. We apply different techniques to recover the cluster mass profiles, evaluating several systematic uncertainties that affect our X-ray mass reconstruction. We present and discuss the cosmological constraints obtained after this analysis. Moreover, I will present recent results we obtained from the analysis of the baryonic content of 52 X-ray luminous galaxy clusters, observed with Chandra in the redshift range 0.3-1.273, on the cosmological parameters Ω_m, ΩΛ and w. » topINS - "Innovations in spectroscopy" M.H. Fabricius, S. Barnes, R. Bender, N. Drory, D. Fisher, F. Grupp, G.J. Hill, U. Hopp, P.J. MacQueen, R. Saglia Kinematics across bulge types of spiral galaxies investigated with longslit spectra and VIRUS-W, a future integral field unit spectrograph (Talk)There is an increasing amount of evidence that early type spiral galaxies host at least two different kinds of bulges - classical bulges and pseudo bulges. While the former are believed to have formed through merging, secular evolution probably plays a predominant role in the formation of the latter. In order to conduct a detailed analysis of the kinematically cold structure of pseudobulges, spectral resolutions down to few tens km/s are needed. So far, few spectrographs with sufficient spectral resolution are equipped with an integral field unit which provides a field of view large enough to cover the bulge regions of local spiral galaxies. We will first show first results from a program that uses longslit spectra taken with the Low resolution spectrograph at the Hobby-Eberly Telescope to examine the bulge regions of 40 local spiral galaxies which were classified as either classical bulges or pseudobulges according to their morphological structure. We find that the class of pseudobulges indeed seems to form a kinematically different class than classical bulges do. Finally we present the design, layout and first laboratory tests of VIRUS-W, a fiber based Integral Field Unit spectrograph. This instrument is built for flexible use at different telescopes, and in particular for the new 2 m telescope on Mount Wendelstein in the Bavarian Alps. Based on the VIRUS spectrograph for the HETDEX experiment, the proposed instrument has a fiber head consisting of 267 optical fibers. The large angular field of view of 150 × 75 arcseconds will allow full coverage of the bulge regions of most local late type galaxies in one or two pointings. The instrument will offer two different resolution modes. A R ~ eq 6800 mode with 850 Å and 515 Å wavelength coverage will be dedicated to the study of bulge kinematics. A second R  ~ eq 2500 with the coverage 4750 Å-5600 Å will give insight into their stellar populations and star formation histories. » topCOS - "Recent advances in cosmology" C. Fechner The spectrum of the intergalactic UV background from QSO absorption lines (Talk)Since the intergalactic medium is highly ionized by the UV background radiation, knowing its spectral energy distribution is essential to study the physical properties of the IGM. We present a simple approach to constrain the spectrum of the UV background by metal absorption systems, and investigate systematically how the estimated physical parameters, like the metallicity, depend on the spectral shape of the ionizing radiation. First results at z ~ 2-3 indicate that the background radiation may be rather soft at this redshift. » topISM - "Dynamical processes in the interstellar medium" C. Federrath, J. Duval, R. Klessen, W. Schmidt, M.-M. Mac Low Solenoidal versus compressive turbulence forcing in simulations and observations (Talk)We compare the statistics of supersonic turbulence obtained in high-resolution numerical experiments with observational data measured in the ISM. Our main focus is on a systematic comparison of solenoidal (divergence-free) and compressive (curl-free) turbulence forcing. Observational data indicate that turbulence in the ISM exhibits both signatures of mainly solenoidal forcing and signatures of mainly compressive forcing depending on the region under consideration. In particular, expanding shells produced by the feedback of massive stars show turbulence statistics similar to the statistics obtained in our numerical models of purely compressive forcing. In contrast, solenoidal forcing appears to be better consistent with observations of more quiescent regions devoid of strong star formation activity. » topISM - "Dynamical processes in the interstellar medium" J. Feige, D. Breitschwerdt, B. Fuchs, C. Dettbarn How does the Local Bubble connect with the 60Fe anomaly in the hydrogenetic ferromanganese crust? (Talk)The deep oceans crust 237KD analysed by Knie et al. (2004) shows a significant increase of the radioisotope 60Fe 2.2 Myr ago. Since 60Fe is produced in supernova (SN) explosions, it is assumed that one or more SNe must have exploded in the solar vicinity to eject enough enriched material to be deposited on earth. The LB, an X-ray emitting H i deficient cavity in the local ISM, was presumably produced by 14-20 SN explosions in a moving group around 10-15 Myr ago (Fuchs et al. 2006), which crossed the solar neighbourhood. Calculating backwards in time we find that the trajectories of this group had a minimal distance of about 65 pc around 2.2 Myr ago. In order to determine the fraction of 60Fe raining down on Earth, we tested a SN model developed by Kahn (1998), which describes the expansion of a SN shell in an ambient medium, which was modified by a previous SN explosion. We thus compute analytically the time the SN remnant shell takes to hit the Earth and how much 60Fe will be deposited there as a function of time. We find that our calculations can reproduce the 60Fe measurements, and in particular the peak deposition, fairly well. » topISM - "Dynamical processes in the interstellar medium" H. Fichtner, K. Scherer Heating of the local interstellar medium by leaking of energetic astrospheric particles (Talk)The interaction between a stellar wind and the neutral interstellar medium produces high energetic neutral and ionised particles. These particles penetrate into the local interstellar medium, where they start to interact with it. We show here first results of the interaction of energetic neutral atoms (ENAs) and anomalous cosmic rays (ACRs) with the the local interstellar medium close to astrospheres. » topISM - "Dynamical processes in the interstellar medium" V. Firpo, G. Bosch, G.F. Hägele, A.I. Díaz, R. Díaz, N. Morrell Internal kinematic and physical properties in a BCD galaxy: Haro 15 in detail (Poster)We present a detailed study of the kinematic and physical properties of the ionized gas in multiple knots of the blue compact dwarf galaxy Haro 15. Using echelle and long slit spectroscopy data, obtained with different instruments at Las Campanas Observatory, we study the internal kinematic and physical conditions (electron density and temperature), ionic and total chemical abundances of several atoms, reddening and ionization structure. Applying direct and empirical methods for abundance determination, we perform a comparative analysis between these regions. On the other hand, our echelle spectra show complex kinematics in several conspicuous knots within the galaxy. To perform an in-depth 2D spectroscopic study we complete this work with high spatial and spectral resolution spectroscopy using the Integral Field Unit mode on the Gemini Multi-Object Spectrograph instrument at the Gemini South telescope. With these data we are able to resolve the complex kinematical structure within star forming knots in Haro 15 galaxy. » topCOS - "Recent advances in cosmology" J. Forero-Romero, G. Yepes, F. Prada, S. Gottlöber Understanding high redshift Lyman-alpha emitters (Talk)Lyman-alpha emitting galaxies (LAEs) provide a unique window on the high redshift Universe and the early stages of galaxy evolution. Nevertheless, the physical properties of observed LAEs are not completely constrained. The largest uncertainty comes from the estimation of the amount of Lyman-alpha photons that can escape the emitting galaxy. In this talk, I will present a statistical study of the intrinsic Ly-alpha and UV emission between redshifts 5 and 6 in the MareNostrum galaxy formation simulation, currently the largest simulation which includes simultaneously gas, dark mater and radiative processes, in a 50 h-1 Mpc box with 2 billion particles. I will present estimations of the Lyman-alpha photon escape fraction for the most resolved galaxies in the same cosmological volume, calculated using a Monte Carlo radiative transfer code. I will discuss the assumptions needed on the dust model to be consistent with the observed luminosity functions, as well the influence of the cosmological parameters on the abundance of Ly-alpha emitters at high redshift. » topPLE - "Plenary session" A. Frebel What the most metal-poor stars tell us about the early Universe (Biermann Talk)The chemical evolution of the Galaxy and the early Universe is a key topic in modern astrophysics. Since the most metal-poor Galactic stars are the local equivalent of the high-redshift Universe, they are being employed to reconstruct the onset of the chemical and dynamical formation processes of the Galaxy, the origin and evolution of the elements, and associated nucleosynthesis processes. They also provide constraints on the nature of the first stars and SNe, the initial mass function, and early star formation processes. The discovery of two astrophysically very important metal-poor objects recently lead to a significant advance regarding these topics. One object is the most iron-poor star yet found (with [Fe/H] = -5.4). The other star displays the strongest known overabundances of heavy neutron-capture elements, such as uranium, and nucleo-chronometry yields a stellar age of ~ 13 Gyr. Metal-poor stars, once also identified in dwarf galaxies, are vital probes also for near-field cosmology. Their chemical signatures now suggest that systems like these were building blocks of the Milky Way's low-metallicity halo. This opens a new window to study galaxy formation through stellar chemistry. » topGAL - "Galactic archaeology" A. Frebel, J. Simon, M. Geha, B. Willman Extremely metal-poor stars in ultra-faint dwarf galaxies (Talk)The most metal-poor Galactic halo stars are now frequently used in an attempt to reconstruct the onset of the chemical and dynamical formation processes of the Galaxy. Principally, the same should be possible for other systems such as dwarf spheroidal galaxies, or even smaller, fainter systems such as the recently discovered ultra-faint dwarf galaxies from SDSS. Until recently, no extremely metal-poor stars ([Fe/H]<-3) were known in any of these dwarf galaxies. I will present the discovery of an existing population of extremely metal-poor stars in the new ultra-faint galaxies. From high-resolutions spectra of six selected stars we find evidence that the ultra-faint dwarf galaxy chemical signature strongly resembles that of the Milky Way halo field stars. This lends support for the galaxy formation scenario through hierarchical merging which predicts that small dwarf galaxies are the building blocks of the Galaxy. » topESC - "eScience: new tools for research in astronomy" F. Freistetter Teaching with the Virtual Observatory (Poster)The Virtual Observatory (VO) does not only offer valuable tools for scientists. VO-tools and data also are an excellent resource for teachers in schools and at universities. The students can learn the basic principles of astronomy/physics by using original data directly from the VO. In the framework of the AIDA (Astronomical Infrastructure for Data Access) project and in cooperation with school teachers, we have developed several examples that demonstrate various features of the VO-tools. Tests at different schools show, that the Virtual Observatory can be integrated in physics lessons without problems. » topACT - "Exoplanets, stellar activity, and the star-planet connection" H.-E. Fröhlich, M. Küker, A.P. Hatzes, K.G. Strassmeier On the differential rotation of CoRoT-Exo-2a (Talk)We apply a robust spot model to fit with the Bayesian MCMC technique the light-curve of CoRoT-Exo-2a. The spots are assumed long-living and each has its own rotation period. A model with three circular spots reproduces the basic features of the longitude-time spot coverage map. One of the spots exhibits a noticeably lower rotational frequency than the two others. From the rotational frequencies of the three dark features a differential rotation above 0.11 rad/d follows. This is in rough agreement with theoretical models. Mean field models of angular momentum transport by convection and meridional flow lead to an equatorial rotational frequency which exceeds that of the poles by 0.09 rad/d. » topACT - "Exoplanets, stellar activity, and the star-planet connection" T. Fruth and the BEST team Ground based support for CoRoT with BEST II (Poster)The CoRoT satellite was launched on December 2006 with two goals: to search for extrasolar planets and study the interior structure of stars. So far, six planets and a brown dwarf (with 20 Jupiter masses) have been reported and several results on stellar seismology are published. The BEST II system operates as photometric ground based support to the CoRoT space mission. Located at the Observatorio Cerro Armazones, Chile, the telescope performs a precise photometric variability characterization within the selected CoRoT stellar fields prior to the satellite observations. A large field of view provides the possibility of monitoring several thousands of stars with a precision of a few milimagnitudes. The reached precision allows observations of variable stars and in general transiting Jupiter-sized extrasolar planets. We will report on the present status of the project and latest scientific results in the framework of the CoRoT mission. » topMSC - Plenary session (posters only) A. Gandorfer, P. Barthol, M. Schüssler, S. Solanki, W. Schmidt, V. Martinez Pillet, M. Knölker, A. Title The first SUNRISE science flight (Poster, registered after deadline)In this contribution we will report on the first successfull scientific flight of the SUNRISE balloon-borne solar observatory. On June 8, 2009 the SUNRISE solar telescope was launched on a stratospheric balloon from the swedish ESRANGE space station. The largest solar telescope that ever left ground reached a flight altitude of 37.5 km above ground, allowing for unprecedented views on solar surface magnetic structures. After 6 days of uninterrupted solar observations the observatory landed safely in northern Canada. All systems behaved nominally. More than a Terabyte of data could be collected, which are now being analysed. » topACT - "Exoplanets, stellar activity, and the star-planet connection" S. Gebauer, M. Godolt, J.L. Grenfell, P. Hedelt, P. v. Paris, H. Rauer On the detectability of biomarkers in extrasolar super-earth atmospheres (Poster)The presence of biomarker molecules in the atmospheres of terrestrial planets is usually interpreted within the context of biological activity. However, the instrumental design requirements for the detection of such species are demanding because of the weak signals. In this contribution we present detailed studies of spectral resolutions and signal-to-noise ratios achievable with currently proposed space telescopes for emission and transmission spectra of super-earth planets. » topMSC - Plenary session (posters only) S. Geier, U. Heber, H. Edelmann, L. Morales-Rueda HD 149382 - a close hot subdwarf binary with substellar companion (Poster)The formation of hot subdwarf stars, which are core helium-burning objects situated at the extended horizontal branch, is still not understood. About half of the known hot subdwarf stars reside in close binary systems with short orbital periods between a few hours and a few days. Recently planetary and brown dwarf companions to sdBs in wide orbits have been discovered. We report the discovery of a substellar object orbiting an sdB star within a 2.5 days. This companion not only survived the common envelope phase within the stellar envelope but also helped forming the subdwarf itself. Substellar companions may play a decisive role for the formation of hot subdwarf stars in general. » topHOT - "Magnetic fields in hot stars" M. Gellert, G. Rüdiger Eddy viscosity and turbulent mixing by magnetic pinch-type instability (Talk)The influence of magnetic fields on the evolution of hot stars became of new interest by including magnetic pinch-type instabilities. Such instabilities of a toroidal magnetic field under the influence of differential rotation have been studied in a simplified approach in the cylindrical geometry of hydromagnetic Taylor-Couette flows. A nearly uniform (but not current-free) toroidal field between conducting cylinders with different rotation rates is considered. The resulting angular momentum transport is directed outwards (inwards) for subrotation (superrotation). We obtain magnetic-induced eddy viscosities exceeding the microscopic values by factors of 10-100. This, however, is only true for super Alfv\'enic rotation but not for the standard Tayler instability for slow rotation. The same instability also quenches concentration gradients of chemicals by its dynamic fluctuations. The diffusion coefficient is generated by the Reynolds stress alone and remains always smaller than the magnetic-generated eddy viscosity. The pinch-type instability, therefore, transports more angular momentum than it mixes chemicals. » topCOS - "Recent advances in cosmology" R. Génova-Santos, F. Atrio-Barandela, J.P. Mücket, J.S. Klar The contribution of the kinematic Sunyaev-Zel'dovich Effect from the IGM to the WMAP 5-year data. (Talk)We study the contribution of the kinematic Sunyaev-Zel'dovich effect, generated by the Warm-Hot Intergalactic Medium, to the Cosmic Microwave Background temperature anisotropies in the five-year data of the Wilkinson Microwave Anisotropy Probe. We explore the concordance ΛCDM cosmological model, with and without this kSZ contribution, using a Monte Carlo Markov Chain algorithm. Our model requires one single extra parameter to describe this new component. Our results show that the inclusion of the kSZ signal improves the fit to the data, without significantly altering the best fit cosmological parameters except Ω_b h2. The improvement is localized at multipoles l\ge 500. For the best-fit model, this extra component peaks at l ~ 450 with an amplitude of 129 μK2, and represents 3.1% of the total power measured by the Wilkinson Microwave Anisotropy Probe. A statistically more significant detection requires the wider frequency coverage and angular resolution of the recently started PLANCK mission. » topELT - "The E-ELT - status, timeline, and instrumentation" G. Gilmore How the OWL, Euro-50, ..., became the E-ELT (Talk)Astronomy has a complex response to large collaborations and projects. At a research level they are common, yet controversial. At a project level they are rare, but become essential as budget ambitions expand. Building the single collaboration which merged competing communities and projects into the European Extremely Large Telescope was an interesting example. I will outline the early history, and deduce why it has been such a success. » topGAL - "Galactic archaeology" G. Gilmore Quantitative mapping cold dark matter (Talk)Very large numbers of precision kinematics allow quantitative analysis of the distribution of dark matter on small scales in local dSph galaxies. This tests directly the (otherwise unknown) behaviour of dark matter on small scales, where astroparticle physics may be detectable. I will summarise our current work analysing several thousand precision kinematic data in small dSph galaxies. » topELT - "The E-ELT - status, timeline, and instrumentation" R. Gilmozzi Status of the E-ELT project (Talk)The E-ELT is a project led by ESO on behalf of its 14 member states. The project is midway through Phase B (detailed design), an activity that will result in a Proposal for Construction by end 2010. The requirements for the design, starting point for the current phase, were defined through a community process that led to the convergence of earlier concepts into a single European project: a 42-m adaptive telescope based on a novel 5-mirror design that is scheduled to have first light in 2018. I will report on the status of the Phase B activities, on the basic reference design development, and on future plans. » topISM - "Dynamical processes in the interstellar medium" W.v. Glasow, M. Krause, J. Sommer-Larsen Galactic winds: connection between SN activity, turbulence and galactic outflows (Talk)Star formation in galaxies causes supernova explosions, and thereby both turbulence and, if strong enough, winds or galactic fountains. High star formation rates, outflow features and turbulence are prime characteristics for high-redshift galaxies. Here, we propose 3D hydrodynamics simulations to address the problem, in particular with the aim to find a logical connection between star formation, turbulence and outflow characteristics. As methodological improvements over previous work, we'd like to use a grid-based approach with realistic initial conditions from a cosmological simulation, and account for radiative transfer effects. We will produce realistic models for the galaxy-halo interaction, and clarify, if continuous accretion can occur simultaneously with strong outflow features. » topISM - "Dynamical processes in the interstellar medium" S. Glover Formation of Molecular Clouds: The Complex Interplay between Dynamical and Chemical Processes (Talk)In order to properly compare the predictions of numerical simulations of molecular clouds with the wealth of molecular line data available for real clouds, we need to know not only the density and velocity structure of the model clouds, but also their temperature distribution and their chemical make-up. Attempts have been made to determine this by post-processing the results of isothermal calculations. However, there is growing evidence that this is inadequate. The reason for this is that chemistry, thermal processes and dynamics are all tightly coupled in real clouds: the thermal evolution of a cloud depends on its chemical make-up, the chemical evolution depends on the hydrodynamics, and the hydrodynamics depends on the temperature evolution. In this talk, I will review recent efforts to model this coupled evolution, and discuss what these models can teach us about the nature of real molecular clouds. » topACT - "Exoplanets, stellar activity, and the star-planet connection" M. Godolt, J.L. Grenfell, A. Hamann-Reinus, M. Kunze, U. Langematz, H. Rauer Influence of the spectral stellar flux distribution on atmospheric dynamics of extrasolar Earth-like planets (Poster)Our main goal is to investigate possible Earth-like exoplanet scenarios and spectra taking into account atmospheric dynamics and chemistry. As a first step we use the state-of-the-art 3D General Circulation Model ECHAM5/MESSy (EMAC) to study the influence of spectral flux distributions corresponding to central stars of different spectral type on Earth-like exoplanets. We focus on the atmospheric responses related to surface habitability such as surface temperature, surface wind and precipitation. Preliminary results as well as a comparision with a 1D radiative-convective model will be presented. » topESC - "eScience: new tools for research in astronomy" T. Granzer, F. Breitling, J. Bartus, M. Weber Towards grids of robotic telescopes (Talk)Linking robotic telescopes to a world-wide network offers considerable advantages even well ahead of joining computer resources, simply due to the fact that new fields of ground-based observations become possible: 24 hours continuous observation and weather independency, otherwise only known from space. This talk summarizes current projects and progress. » topACT - "Exoplanets, stellar activity, and the star-planet connection" T. Granzer, K.G. Strassmeier, I. diVarano, M. Weber Chasing a 100 000 stars from a cold place - Ice-T on DomeC (Poster)Ice-T is a double-Schmidt 60 cm telescope particularly designed to operate on the Antarctic plateau, at the Concordia station, Dome C. The extended long observing period together with the big 10k×10k CCD, operated at exposure times of 10 sec, present a true challenge on data handling, storing and transfer. This talk will summarize possible solutions. » topGAL - "Galactic archaeology" E.K. Grebel Satellites of the Milky Way (Talk)In recent years, the number of confirmed satellites of the Milky Way has essentially been doubled thanks to the discovery of new, extremely faint dwarf spheroidals. During the same time period, both the classical and the new companions have been explored in great detail using spectroscopy. In addition to detailed star formation histories obtained largely via deep imaging with the Hubble Space Telescope, the ground-based spectroscopic studies have provided a wealth of information about the detailed chemical composition and the internal kinematics of the dwarfs, primarily by employing stellar optical spectroscopy. Emission-line spectroscopy of H ii regions (of the Magellanic Clouds) and of planetary nebulae in Milky Way satellites has also provided important clues about their evolutionary histories. In this review, I will concentrate on the results of the spectroscopic galactic archaeology' efforts for these dwarfs. The growing number of stars for which individual element abundance ratios are available reveal a complex picture of inhomogeneous enrichment through localized star-formation events at low star formation rates. The chemical properties of the stars in the dwarfs permit us to constrain the contribution of low-mass satellites to the build-up of the Milky Way itself. Moreover, the radial velocity dispersion profiles that are now available for many dwarfs allow yield constraints on their total masses and mass profiles, which in turn has important implications for their evolutionary histories. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" J.L. Grenfell, J. Stock, S. Gebauer, B. Patzer, H. Rauer Effect of CO-oxidation occurring on haematite upon the chemical composition of CO2-dominated atmospheres (Talk)Haematite (Fe2O3) is likely to be present on the surfaces of both Venus and Mars. It is widely recognised in the chemical industry that this mineral can rapidly oxidise gaseous carbon monoxide (CO) into carbon dioxide (CO2) via a heterogeneous chemical mechanism. We assess the impact of this mechanism with regard to CO2-dominated planetary atmospheres. » topGAL - "Galactic archaeology" G. Grohne Morphology of galaxies (Poster)Galaxies come in a variety of morphological shapes. Some are plain elliptical, other show inner structures like rings or spiral arms. I will present some theoretical approaches and simulations using the Gadget2 code by V. Springel to explain the origin of these features. » topMSC - Plenary session (posters only) P. Grunden, D.J. Bomans LSB galaxies among supernova host galaxies (Poster)Due to their high luminosity supernovae (SNe) are easy to detect even at huge distances. Hence they give us the possibility to investigate also faint galaxies. The SAI supernova catalogue contains all known SNe and additional information about their host galaxies. We used the data of these host galaxies to calculate the central surface brightness (μ0) by using an exponential profil for the luminosity distribution. Low Surface Brightness (LSB) galaxies are defined as galaxies fainter than 23 mag arcsec-2 in the B-band. Using this sample of SN host galaxies we found that about 7% of all these galaxies in the local universe (z≤0.05) are LSB galaxies. We discuss this result in the context of LSB galaxy formation and the LSB galaxy contribution to the local baryon density. » topINS - "Innovations in spectroscopy" F. Grupp, T. Udem, F. Lang, U. Hopp, R. Bender FOCES, a testbed for astro comb precision astronomy (Talk)The FOCES Echelle spectrograph shall be used as a testbed for an improved understanding of fiber coupling and the practical use of frequency combs in astronomy. Offering a spectral coverage from 3800Å up to 9000Å and a two pixel resolving power of R = 70 000 FOCES is planned to serve as a laboratory test instrument in the first step and to prove its capabilities at the new 2 m Fraunhofer Teleskop Wendelstein' in the second step of this project. We will present a project outline and the key problems addressed with this talk. » topMSC - Plenary session (posters only) A. Gucsik Cathodoluminescence properties of nanodiamonds: an application to astropysics (Poster, registered after deadline)Primitive meteorites contain abundant (up to 1500 ppm) amounts of nanodiamonds. Two main theories exist for the formation process of the meteoritic nanodiamonds: (1) Chemical vapor deposition (CVD), and (2) shock origin. K2 (Ultradispersed Detonation Diamonds-UDD) nanodiamonds were selected to the cathodoluminescence microscopical and spectroscopical studies. They show characteristic CL spectral features at around 388 (3.1 eV; A-center) and 452 (2.69 eV; N-center) nm, which are good agreement with those of the N-enriched spectral properties of nebula NGC 7027. According to this preliminary laboratory experiment, diamond particles in nebula NGC 7027 may be originated due to explosive processes, i.e., shock wave. » topESC - "eScience: new tools for research in astronomy" B. Gufler, J. Müller, T. Scholl, A. Reiser, A. Kemper Scalable scientific data analysis in the Cloud (Talk)Fast analysis of very large data sets plays a central role in astrophysics as well as in many other e-science disciplines. Moreover, these data sets often do not just consist of a set of unrelated tuples, but contain structures like trees or graphs. Distributing data analysis, e.g. data mining tasks to clusters, Grid or Cloud environments seems to be a promising approach for accommodating interactive data exploration. Inspired by Google's MapReduce approach, we are developing the Pipelined MapReduce framework for Cloud scale data mining, and a scripting language allowing for easy development of distributed applications. In this talk, we will introduce our framework and discuss its impact on scientific data analysis based on a sample application: frequent subtree mining on the Millennium merger trees. » topMSC - Plenary session (posters only) P. Günster, D.J. Bomans Population differences of LSB galaxies in the CFHTLS (Poster)The formation history of galaxies with low surface brightnesses (LSB) is not fully understood by far. In this poster we present the results of an analysis of a testfield from the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). After being detected using pixel thresholding software the galaxies have been fitted by a S'ersic profile to derive photometric data and calculate the surface brightness. The application of the standard selection criterion μ0(B) ≥ 23.0 mag/arcsec2 yielded a sample of LSB candidates that we further examined in the u'g'r' resp. UBV color space. A sizeable subgroup of the galaxies populates a zone in the red part of the color-color diagram. This implies that they can not be considered as homogeneous evolutional branch with the blue galaxies, which are the majority of our LSB detections. Implications for the evolution of LSB galaxies are discussed. » topACT - "Exoplanets, stellar activity, and the star-planet connection" M. Gyergyovits, E. Pilat-Lohinger, Ch. Theis Evolution of protoplanetary disks in binary systems (Talk)We study the evolution of planetary systems around binary stars, once they are established. We are especially interested in the impact of a gaseous disk on the short-term and the long-term dynamics of the planetary system. Therefore we adapted a 2D fluid-dynamical code including self-gravity, for the motion of the disk comoving with the primary star. The location of the embedded planet and the position of the secondary are chosen in agreement with the system Gamma Cephei. We present tests of different implementations and discuss problems, which arise from the interplay of a hydrocode and a N-body solver. We plan to use this code to follow the system's evolution, for a short period of time in order to derive drift rates of the semimajor axis and the eccentricity of the planet for long-term modelling. In a first series of simulations, we vary the orbital elements (semimajor axis, mean anomaly) of the planet, and the masses of the disk and the secondary star. We especially address the evolution of the system near the stability boundaries of the restricted three-body problem, by this shedding light on the impact of a gaseous disk on the long-term stability and evolution of a system like Gamma Cephei. » topCOS - "Recent advances in cosmology" M. Haas, S.P. Willner, F. Heymann, M.L.N. Ashby, G.G. Fazio, B.J. Wilkes, R. Chini, R. Siebenmorgen, D. Stern Clustering of red galaxies around the \bf z = 1.53 quasar 3C 270.1 (Talk)In the paradigm of hierarchical galaxy formation, luminous radio galaxies mark mass assembly peaks that should contain clusters of galaxies. Observations of the z = 1.53 quasar 3C 270.1 with the Spitzer Space Telescope at 3.6-24 μm and with the 6.5 m MMT in the z' and Y bands allow the detection of potential cluster members via photometric redshifts. Compared with nearby control fields, there is an excess of ~ 11 extremely red objects (EROs) at 1.33 ≤ z_phot ≤ 1.73, consistent with a protocluster around the quasar. The spectral energy distributions of 3/4 of the EROs are better fitted with passive elliptical galaxies than with dust-reddened starbursts, and of four sources well detected on an archival Hubble Space Telescope (HST) snapshot image, all have undisturbed morphologies. However, one ERO, not covered by the HST image, is a double source with 0.8" separation on the z' image and a marginal (2σ) 24 μm detection indicating a dust-enshrouded starburst. The EROs are more luminous than L* (H = -23.6 AB mag at z ~ 1.5). » topPLE - "Plenary session" M. Haehnelt Mapping out the Universe on its largest scales (Talk)Probing dark matter and galaxies with Lyman-α in absorption and emission: I will present recent results (i) from Lyman-α forest data with regard to the question of how cold dark matter is, and (ii) from a ultra-deep spectroscopic survey for Lyman-α emission with regard to the host galaxies of DLAS and the assembly of Milky-way type galaxies. I will also briefly discuss the proposed ultra-stable high-resolution spectrograph CODEX for the E-ELT. » topISM - "Dynamical processes in the interstellar medium" G. Hägele, A.I. Díaz, M.V. Cardaci, E. Terlevich, R. Terlevich Circumnuclear star-forming regions in NGC 3310 (Talk)Gas and star velocity dispersions have been derived for eight circumnuclear star-forming regions (CNSFRs) and the nucleus of the spiral galaxy NGC 3310 using high resolution spectroscopy in the blue and far red. Stellar velocity dispersions have been obtained from the Ca ii triplet in the near-IR, using cross-correlation techniques, while gas velocity dispersions have been measured by Gaussian fits to the Hβ λ 4861 Å and [O iii] λ 5007 Å emission lines. The CNSFRs stellar velocity dispersions range from 31 to 73 km s-1. These values, together with the sizes measured on archival HST images yield upper limits to the dynamical masses for the individual star clusters between 1.8 and 7.1 × 106 Msun and upper limits to the masses for the whole CNSFR between 2. × 107 and 1.4 × 108 Msun, and is 5.3 × 107 Msun for the nucleus inside the inner 14.2 pc. The masses of the ionizing stellar population responsible for the H ii region gaseous emission have been derived from their published Hα luminosities and are found to be between 8.7 × 105 and 2.1 × 106 Msun for the star-forming regions, and 2.1 × 105 Msun for the galaxy nucleus therefore constituting between 1 and 4 per cent of the total dynamical mass. The ionized gas kinematics is complex; two different kinematical components seem to be present as evidenced by different widths and Doppler shifts. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" R. Hammer, Z.E. Musielak, S. Routh, S. Subramaniam Propagation of waves along magnetic flux tubes in the solar atmosphere (Talk)Waves along magnetic flux tubes contribute to the heating and vigorous dynamics of the outer solar atmosphere, provided that the wave frequency exceeds a certain cutoff frequency below which no energy can be transported. The cutoff frequency depends on the type of wave, on the thickness of the flux tube, and on the density and temperature stratification of the atmosphere. Until recently, it has been derived in closed form only for thin tubes in an isothermal atmosphere. We have relaxed these restrictions and show that tube thickness as well as temperature gradients lead to cutoff frequencies that vary along the tube. The results will be discussed for both transverse and torsional Alfv\'en waves along magnetic flux tubes embedded in an atmosphere representative of the solar photosphere and chromosphere. » topCOS - "Recent advances in cosmology" S. Harfst, D. Groen, S. Portegies Zwart CosmoGrid: simulating the Universe across the Globe (Talk)The universe has been expanding since the beginning of space and time. The best model to date that describes this evolution is called Λ cold dark-matter cosmology (ΛCDM), according to which the universe is about 13.7 billion years old and comprises of ~ 28% matter and some 72% dark energy indicated by the letter Λ. About 85% of the matter are in the form of non-baryonic dark matter interacting only by gravity with the remaining fraction of baryonic matter. The nature of dark matter is unknown but the way in which dark matter interacts is rather simple, and well understood. As a result, we can effectively study dark matter by simulations and use the results of these to understand observations and to make predictions. One of the most favorable techniques to study the formation of large scale structures in the universe is by means of gravitational N-body simulations. The computational techniques with which such simulations are performed are well developed since the late 1990s and a number of parallel and highly optimized algorithms have been developed for this task. Nevertheless, cold dark-matter N-body simulations are challenging, in particular because the computer resources for performing such large simulations are often not directly available for an extended period of time, except if one monopolizes the use of a local supercomputer. The simulation method, however, is excellently suited for distributed high-performance computing, in which two or more computers at different locations run concurrently as one large computer. » topGAL - "Galactic archaeology" R. Haschke, E. Grebel Metallicity distribution function and three dimensional maps of the Magellanic Cloud (Poster)In a series of papers analysing lightcurves, Kovacs et al. (1995, 1996) found relations between the Fourier parameter φ31, the period and the metallicity of RR Lyrae stars. The metallicity is used to calculate the absolute magnitude (Clementini et al. 2003) and to obtain distances to each single RR Lyrae star present in the OGLE data of the Magellanic Clouds (MCs). The metallicities are used to derive metallicity distribution functions of the old populations of the MCs. For the Cepheids, found by OGLE, the relations by Sandage (2004) and Tammann (2008) are used to compute the absolute magnitudes and to estimate the distances. These two very different populations (RR Lyrae are about 10 Gyr old, while Cepheids are only a few 100 Myr in age) are used to obtain in three dimensional maps that show the depth and distribution of each group in both clouds. For the SMC the result of these computations shows a large depth extent of about 20 kpc. Furthermore the maps show a shift between the two populations. The RR Lyrae are more evenly distributed while the Cepheids seem to be pushed from the western parts backwards and centerwards. The LMC has a depth of about 15 kpc and both populations show a similar distribution. But the Cepheids are in general about 5 kpc farther away. This offset is probably connected to the unresolved short and long distance scale problem. » topGAL - "Galactic archaeology" R. Haschke, E. Grebel Reddening maps of the Magellanic Clouds determined from red clump stars (Poster)We present reddening maps of the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC) obtained from red clump stars observed by the Optical Gravitational Lensing Experiment (OGLE). The OGLE collaboration has obtained photometric data of the Galactic centre, the LMC and the SMC. Over several years the same areas of the sky have been observed repeatedly to obtain lensing events. As a side-product very precise photometric maps of the regions became available. Subramaniam (2005) used the second data release of OGLE to calculate reddening maps for the central region of the LMC. First she divided the field in more than 1000 sub-fields. Then the distribution of the red clump stars, in (V-I) colour, is fitted with a Gaussian plus a second order polynom. The maximum of the function represents the mean colour (V-I)_measured of the clump. With the relation E(V-I) = (V-I)_measured-(V-I)0 the reddening is estimated. The adopted value for the mean unreddend colour of the red clump in the LMC is (V-I)0 = 0.92. Olsen & Salyk (2002) showed that (V-I)0 has a metallicity dependent but robust value. In our work the new OGLE III release is used, which covers a much greater area of the LMC and SMC than the second data release. The method used by Subramaniam (2005) is applied to the new data and reddening maps of nearly the entire area of both clouds are obtained. For the LMC the same mean (V-I)0 value is adopted for the red clump stars, while for the SMC (V-I)0 = 0.89 is assumed. The calculations lead to an overall low value of the reddening in each cloud. While in the SMC three pronounced areas of higher reddening are visible, 30 Doradus is dominant in the LMC. The distribution found is generally in good agreement with data from infrared maps and CO studies (compare to Dobashi et al. 2008, 2009). Our reddening maps will be made available through a web interface. This project is the first step in larger study aiming at the determination of the metallicity distribution function and of the three dimensional structure of the Clouds. » topACT - "Exoplanets, stellar activity, and the star-planet connection" A. Hatzes Extracting signals from the noise: the limits of radial velocity searches for extrasolar planets (Talk)The radial velocity (RV) method has had spectacular success at discovering over 300 extrasolar planets in the past two decades. A current radial velocity precision of 1-2 m/s is already finding Neptune (15a-20 M_Earth) and Super Earth (5-10 M_Earth) mass planets. New wavelength calibration technologies, such as the laser comb, may increase the RV measurement precision to a few tens of cm/s, giving hope that an Earth mass planet in the habitable zone of a G-type star may one day be discovered. However, RV measurements are limited by intrinsic stellar variability, foremost that caused by stellar activity. The RV jitter' due to stellar activity can range from 1 to several hundreds m/s, depending on the activity level of the star and this far exceeds the RV amplitude of an exo-earth in the habitable zone of a G-type star. I will present strategies for overcoming this activity jitter and limits of the RV methods. I will show several examples of planets around active stars including some results from the CoRoT space mission. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" B. Heber, J. Gieseler, H. Fichtner, A. Kopp, P. Dunzlaff, M. Potgieter, S. Ferreira Modulation of galactic cosmic ray protons and electrons during an unusual solar minimum (Talk)During the latest Ulysses out-of-ecliptic orbit the solar wind density, pressure and magnetic field strength have been the lowest ever observed in the history of space exploration. Since cosmic ray particles respond to the heliospheric magnetic field in the expanding solar wind and its turbulence, the weak heliospheric magnetic field and low plasma density and pressure are expected to cause the smallest modulation since the 1970's. In contrast to this expectation, the galactic cosmic ray proton flux at 2.5 GV measured by Ulysses in 2008 does not exceed the one observed in the 1990's significantly, while the 2.5 GV galactic cosmic ray electron intensity exceeds the one measured during the 1990's by 30-40%. At true solar minimum conditions, however, the intensities of both electrons and protons are expected to be the same. In contrast to the 1987 solar minimum, the tilt angle of the solar magnetic field has remained at about 30 degree in 2008. In order to compare the Ulysses measurements during the 2000 solar magnetic epoch with those obtained 20 years ago, the former have been corrected for the spacecraft trajectory using latitudinal gradients of 0.25% deg-1 and 0.19% deg-1 for protons and electrons, respectively, and a radial gradient of 3% AU-1. In 2008 and in 1987, solar activity, as indicated by the sunspot number, was low. Thus, our observations confirm the prediction of modulation models that current sheet and gradient drifts prevent the galactic cosmic ray flux to rise to typical solar minimum values. In addition, measurements of electrons and protons allow us to predict that the 2.5 GV galactic cosmic ray proton intensity will increase by a factor of 1.3 if the tilt angle reaches values below 10 degree. » topISM - "Dynamical processes in the interstellar medium" M. Hegmann, F. Levrier Non-LTE line formation in clumpy and turbulent molecular clouds: correlated velocity and density fluctuations (Poster)We study the formation of interstellar CO lines in a medium with stochastic velocity and density fluctuations and finite correlation lengths. We account for correlations between the density and velocity field by assuming that the nonthermal velocity dispersion scales as a power-law of the density. We then derive a generalized radiative transfer equation, which we self-consistently solve alongside rate equations, to treat the complete NLTE problem in plane-parallel slab geometry. Our results show, that correlations between the density and turbulent velocity field have to be taken into account for an analysis of highly resolved spectral data. In particular, correlation effects lead to a strong enhancement of the line wings compared to the intensity in the line center. » topACT - "Exoplanets, stellar activity, and the star-planet connection" R. Heller, B. Jackson, R. Barnes, R. Greenberg, D. Homeier Tidal effects on brown dwarfs: a possible explanation for the anomalous temperature reversal in the eclipsing binary 2MASSJ05352184-0546085 (Talk)2MASS J05352184-0546085 (2M0535-05) is the only known eclipsing brown dwarf (BD) binary, and so may serve as an important benchmark for models of BD formation and evolution. However, theoretical predictions of the system's properties seem inconsistent with observations: i. The more massive (primary) component is observed to be cooler than the less massive (secondary) one. ii. The secondary is more luminous (by ~ 1024 W) than expected. Previous explanations for the temperature reversal have invoked reduced convective efficiency in the structure of the primary, connected to magnetic activity and to surface spots, but these explanations cannot account for the enhanced luminosity of the secondary. Previous studies also considered the possibility that the secondary is younger than the primary. We study the impact of tidal heating to the energy budget of both components to determine if it can account for the observed temperature reversal and the large luminosity of the secondary. We also compare various plausible tidal models to determine a range of predicted properties. We apply two versions of two different, well-known models for tidal interaction, respectively: i. the constant-phase-lag' model and ii. the constant-time-lag' model and incorporate the predicted tidal heating into a model of BD structure. The four models differ in their assumptions about the rotational behavior of the bodies, the system's eccentricity and putative misalignments ψ between the bodies' equatorial planes and the orbital plane of the system. The contribution of heat from tides in 2M0535-05 may be large enough to account for the discrepancies between observation and theory. The observed luminosity increase of the secondary can be reproduced when we consider contributions from the eccentricity decay and rotational synchronization over a range of the BDs' tidal quality factor Q or time lags τ and possible obliquities ψ2 of the secondary. Tidal heating may be responsible for the surprising temperature reversal within 2M0535-05. The heating would have slowed down the BDs' shrinking processes and the temperature decrease after the birth of the system ~ 1 Myr ago. More complete modeling of the evolution of these BDs that consistently incorporate tidal effects are required to corroborate our results. Our models suggest connections between the orbital and tidal properties of BDs, providing constraints on tidal dissipation parameters for BDs. For example if tides are indeed responsible for the observed temperature reversal, then we expect few old BD binaries in non-circular orbits. Measurements of the Rossiter-McLaughlin effect for 2M0535-05 can also provide constraints on Q. » topCOS - "Recent advances in cosmology" G. Hensler, K. Sternig, A. Boselli, W.W. Zeilinger Building-up galaxy clusters: where are the survivors of ram-pressure-stripped galaxies? (Talk)Galaxies that fall into the gravitational potential of galaxy clusters experience the existence of hot tenuous intra-cluster gas. Ram pressure pushs the interstellar medium out of galaxies, easier for the low-mass galaxies and therefore already in the outermost cluster regions. Normal spiral galaxies are observed in the act of gas stripping within the denser intra-cluster medium. Numerical models over the last years are performed with different numerical schemes and match almost equally with the observations of ram-pressure stripping (RPS) galaxies. Since such models almost always consider only constant ram-pressure conditions they finish at the maximum effect of ram pressure and mostly do not follow the further path of stripped galaxies to their apocentric orbit when the ram pressure declines. There, however, the appearance of galaxies with RPS-truncated gaseous disks lacks in the outskirts of clusters. Their radial distribution should clearly differ from that of normal morphologies. Theoretically, two possible outcomes can be imagined: One possibility is that additional dispersal effects, like e.g. Kelvin-Helmholtz instability or heat conduction, withdraw the remaining gas and produce disk-dominated S0s. If gaseous disks survive the RPS they could also re-organize their gas distributions by radial pressure effects and can be identified as H i-deficient spirals. We studied both candidates in the Virgo cluster and will present their radial distribution with a clear conclusion. » topGAL - "Galactic archaeology" F. Hessman Deriving the surface densities of self-gravitating thin disks (Poster)The standard method of computing the surface density of thin, axisymmetric, self-gravitating disks from their rotation curves is due to Toomre (1963). The algorithm uses the first derivative of the observed rotation curve and assumes the disk is infinite in size. Other methods have their own problems, like fitting truncated infinite series to the data. Using the splitting method of Pierens & Hure (2004) and by partially integrating either the Toomre integral for infinite disks or its re-formulation for finite disks due to Garcia, Manko & Sibgatullin (2005), one obtains simple integral equations for the surface density as a function of the disk's rotation curve whose integrands contains elliptical integral functions but are everywhere finite and continuous and hence easily integrated numerically. » topESC - "eScience: new tools for research in astronomy" F. Hessman (representing the IVOA Semantics Working Group) The IVOA vocabulary effort - moving beyond unified content descriptors (Talk)As the astronomical information processed within the Virtual Observatory becomes more complex, there is an increasing need for a more formal means of identifying quantities, concepts, and processes not confined to things easily placed in a FITS image, or expressed in a catalogue or a table. The IVOA semantics working group has proposed a standard format for vocabularies based on the W3C's Resource Description Framework (RDF) and Simple Knowledge Organization System (SKOS). By adopting a standard and simple format, the IVOA will permit different groups to create and maintain their own specialised vocabularies while letting the rest of the astronomical community access, use, and combine them. The use of current, open standards ensures that VO applications will be able to tap into resources of the growing semantic web. Several examples of useful astronomical vocabularies are described, including work on a common IVOA thesaurus intended to provide a semantic common base for VO applications. » topMSC - Plenary session (posters only) F. Hessman, S. Dreizler, M. Hundertmark Remote observations with the MONET telescopes - a status report (Poster)This poster gives an overview of the remote use of the MONET telescopes by an international community of research, student, and educational users. The technical and administrative challenges of maintaining the hard- and software as well as managing such a heterogeneous set of users is discussed. » topACT - "Exoplanets, stellar activity, and the star-planet connection" D. Homeier, B. Freytag, F. Allard Modelling convective transport in substellar atmospheres based on radiation hydrodynamic simulations (Poster)Convection plays a pre-eminent role in the structure of ultracool atmospheres, starting with the fully-convective late M dwarfs, in which a major part of the emergent energy is carried by convection well into optically thin regions of the atmosphere. While the convectively unstable regions recede again into deeper layers with further decreasing effective temperatures, they are expected to be responsible for the mixing processes that allow condensate clouds to be supported, and that lead to observable deviations from chemical equilibrium mixtures in cooler very-low-mass stars, brown dwarfs and gas giant planets. We present simulations of the velocity field for such atmospheres based on radiation hydrodynamic calculations with the CO5BOLD code, showing overshoot activity well above the Schwarzschild boundary, and a high-reaching turbulence pattern dominated by gravity waves. Feeding these results into the classical 1D atmosphere code PHOENIX, we can provide quantitative predictions of the cloud opacity for brown dwarf and planetary mass objects and of the spectral signatures of tracers of non-equilibrium chemistry, such as carbon monoxide and ammonia. » topHOT - "Magnetic fields in hot stars" S. Hubrig, M. Schoeller The present status of our knowledge of magnetic fields in massive hot stars (Talk)Magnetic fields have been directly measured in a number of massive early B and O stars. The knowledge of the magnetic field topology of massive stars at different evolutionary stages is important to understand the underlying magnetic field generation mechanism(s). We will review the present status of magnetic field studies along with the results of theoretical modeling. » topACT - "Exoplanets, stellar activity, and the star-planet connection" M. Hundertmark, F.V. Hessman, S. Dreizler Information driven sampling of gravitational microlensing lightcurves (Poster)Galactic gravitational microlensing events magnify the light of source stars located in the Galactic bulge. The high sensitivity for detecting low-mass companions at distances of several kpc makes microlensing an ideal tool for extending our knowledge about the frequency of extrasolar planets. The aim of our work is to illustrate how an optimal sampling of gravitational microlensing lightcurves can be achieved in the sense of the Fisher Information Matrix. This is particularly relevant for planning follow-up strategies within international microlensing collaborations and can help to identify planetary companions around microlenses as soon as possible. For this purpose, we have used Monte-Carlo simulations for determining the Fisher matrix, whose diagonal entries provide lower bounds for the parameter uncertainties. Its evolution for differently sampled lightcurves indicates not only how observational strategies can be optimized, but also when first reliable estimates for a point lens point source model can be obtained. » topCOS - "Recent advances in cosmology" H. Israel, T. Erben, T.H. Reiprich The 400 d Galaxy Cluster Survey Weak Lensing Programme (Talk)Evolution in the mass function of clusters of galaxies sensitively traces cosmological structure formation. In particular, the number density of massive clusters as a function of redshift can be used to constrain cosmological parameters. We aim at deriving a robust mass function by a detailed comparison of cluster masses derived from observations of their X-ray and weak lensing signals. Based on the recent 400 d survey (Vikhlinin et al. 2007) of serendipitous ROSAT/PSPC detections, we therefore use an X-ray flux- and luminosity-limited subsample of clusters at z>0.35 for which we conduct a weak lensing survey. As a starting point for this survey, we present our observations of eight clusters with MMT/Megacam to which we applied the Erben et al. (2005) reduction method for wide-field imaging data. We performed a detailed weak lensing study of one of these clusters, CL0030+2618 at z = 0.5, and find good agreement of the resulting mass estimate M200 ~ 5× 1014 Msun to the X-ray analysis by Vikhlinin et al. (2009). » topMSC - Plenary session (posters only) R. Jacob, C. Sandin, D. Schönberner, M. Steffen Modeling extragalactic Planetary Nebulae: structure and expansion properties (Poster)Technological progress in spectroscopy and imaging of extragalactic Planetary Nebulae prompted us to investigate, for the first time, the structure and expansion properties of extragalactic Planetary Nebulae by means of detailed 1D-radiation-hydrodynamics simulations. Specifically, we investigate how the basic nebular structures and kinematics depend on the adopted metallicity Z. As the central-star wind luminosity decreases with Z, ionization-driven expansion caused by the stellar radiation field dominates in shaping PNe with lower metallicity. At the same time, the nebulae with lower metallicity expand faster than their more compact galactic counterparts due to their reduced radiative cooling. By computing observable quantities like surface brightnesses, emission-line strengths, and volume-integrated line profiles, a detailed comparison with recent high resolution spectroscopic observations of Local group PNe and 11 bright Virgo cluster PNe has been carried out. In fact, our models can explain the unexpected empirical finding that the expansion velocities of Planetary Nebulae, determined from the emission line widths, are virtually independent of their metallicity and the age of the progenitor stellar population. » topINS - "Innovations in spectroscopy" T. Jahn, M.M. Roth, H.-G. Loehmannsroeben, A. Kelz, M. Kumke, D. Steinbrück Multi-channel spectroscopy for distributed fiber-optical chemical sensing (Poster)The interdisciplinary innovation center innoFSPEC, which is a joint initiative between the AIP and the University of Potsdam, Physical Chemistry group (UPPC), focuses on research in fiber-optical spectroscopy and sensing. Two of the major fields of the future research groups, namely Multi-Channel Spectroscopy and Innovative Fiber-Sensing, are being explored in this work, which is a Master of Science (MSc) project at the FH Brandenburg. The aim of the work is to develop a 2-dimensional optical fiber sensor to simultaneously measure spatially resolved chemical parameters, e.g. pH, with high throughput. Thus, technical expertise in fiber-based multi-channel spectroscopy from astrophysics is transferred to fiber-optical sensing in chemistry. » topINS - "Innovations in spectroscopy" K. Jahnke, K. Inskip, H.-W. Rix, C.Y. Peng Dynamical masses of lensed quasar host galaxies at z ~ 2: Near Infrared Integral Field Spectroscopy with Laser AO (Talk, registered after deadline)We present initial results from a campaign using the near infrared integral field unit SINFONI at the ESO VLT in combination with the PARSEC laser guide star adaptive optics module. In order to study black hole to galaxy mass scaling relations out to the early Universe we attempt to estimate dynamical masses by tracing Hα through the systems. Our targets are gravitationally lensed quasar host galaxies at redshifts 1.6 to 2.3, that magnify flux and linear scales of the host galaxy targets. Still we deal with linear scales of <1" and extremely faint line fluxes. We developed methods for data reduction and treatment for these complex data and still report first successes in this project. » topMSC - Plenary session (posters only) K. Jahnke, M. Cisternas, K. Inskip, and the COSMOS collaboration No evolution in the MBH-M_*,total relation over the last 9 Gyrs (Poster, registered after deadline)We investigate 10 QSO host galaxies at 1Ba\frac3{n}, one can obtain ωeff_Λ<-1, which corresponds to a universe dominated by phantom dark energy. » topPLE - "Plenary session" G. Kauffmann The chemical and kinematical properties of galaxies and their black holes throughout cosmic time (Review Talk)Absorption lines in the rest-frame optical spectra of galaxies provide a wealth of information about the ages and metallicities of the constituent stars. Emission lines provide measures of the ionizing flux from young stars and diagnostics of the presence of a central AGN. A new generation of large spectroscopic surveys has provided a wealth of physical information for galaxies out to redshifts of 1 and beyond, and have led to improved understanding of the physical processes regulating the evolution of galaxies over cosmic time. I will review some of the highlights of this rapidly expanding field. » topPLE - "Plenary session" H.U. Käufl VLT-CRIRES, good vibrations (Highlight Talk)Near-Infrared high resolution spectroscopy offers new and innovative observing opportunties for astronomy. The "traditional" benefits of IR-astronomy - strongly reduced extinction and availablity of adaptive optics - more than offset for many applications the compared to optical astronomy strongly reduced sensitivity. Especially in high resolution spectroscopy interferences by telluric lines can be minimized. Moreover many important atoms for abundance studies can be accessed in the NIR. A fundamentally new spectral feature available for quantitative spectroscopy are the molecular rotational-vibrational transitions which allow for fundamentally new studies of condensed objects and atmospheres. This is also an important complement to radio-astronomy, especially with ALMA, where molecules are generally only observed in the vibrational ground state. Rot-vib transitions also allow high precision abundance measurements of isotopic ratios, fundamental to understand the thermo-nuclear processes in stars beyond the main sequence. Quantitative modelling of atmospheres has progressed such that the unambigous interpretation of IR-spectra is now well established. In combination with adaptive optics spectro-astrometry is even more powerful and with VLT-CRIRES a spatial resolution of better than one milli-arcsecond has been demonstrated. Some highlights and recent results will be presented: our Solar system, extrasolar planets, star- and planet formation, stellar evolution and the formation of galactic bulges. » topINS - "Innovations in spectroscopy" C. Kehrig, J.M. Vílchez, S.F. Sánchez, E. Telles, E. Pérez-Montero, D. Martín-Gordón An integral field view of the massive star feedback and the ionized gas in H ii galaxies (Talk)H ii galaxies are gas-rich, metal-poor dwarf systems that have experienced intense recent or ongoing violent star formation. The main goal of this work is to study the interplay between the massive star formation feedback processes and the ionized interstellar medium, as well as the stellar population content in nearby H ii galaxies. In this talk we will present results from integral field spectroscopy of the H ii galaxy II Zw 70. Maps of properties of the ionized interstellar medium and relevant emission lines will be presented. Observations were taken in the optical spectral range from λ 3700-6800 Å with the Potsdam Multi-Aperture Spectrophotometer (PMAS) attached to the 3.5 m telescope at Calar Alto Observatory. » topINS - "Innovations in spectroscopy" A. Kelz et al. 2001-2010: a PMAS decadal review (Talk)Since its commissioning in 2001, PMAS, the Potsdam Multi-Aperture Spectrophotometer, that was developed and built at AIP, is in operation at the Calar Alto 3.5 m telescope. PMAS is a dedicated integral field spectrograph, with optimized optics to cover the wavelength regime between 350 and 900 nm. Originally, PMAS featured an Integral-Field Unit with a 16× 16 element lens array coupled to optical fibers, which provides seeing-limited sampling. Over the years, PMAS was used for a diverse range of scientific projects, ranging from studies of planetary nebulae, evolution of galaxies to dark matter distribution. Additionally, PMAS was continuously upgraded and used as a technological testbench. Examples are the introduction of a nod-shuffle mode (2002) for beam switching and improved sky background subtraction and a scanning Fabry-P\'erot etalon (PYTHEAS mode, 2003). The PPak-wide-field IFU (2005), features a bare fiber bundle for an expanded FOV with a footprint of 64× 74 arcsec on the sky. In 2008, a 3D-spectropolarimetric observing mode was added. The latest development is the planned upgrade of the CCD detector, which increases the PMAS efficiency even further and doubles the wavelength coverage. The presentation will review these technological developments and present selected science cases done with PMAS during these last years. Also, an outlook on planned activities in the next decade will be given. » topELT - "The E-ELT - status, timeline, and instrumentation" M. Kissler-Patig Science Drivers for the E-ELT (Talk)I will present the process by which the science drives the design of the E-ELT project. The role of the Science Working Group will be highlighted, in particular the purpose of the Design Reference Mission. In parallel, a broad community input was received through the Design Reference Science Plan, which I will summarise. These science cases were complemented by an ALMA-ELT workshop looking at synergies, and by a number of science cases prepared by the instrument teams as part of several phase A studies. Finally, this effort is complemented by some end-to-end simulations of cases aimed at defining the operations requirements. » topHOT - "Magnetic fields in hot stars" L.L. Kitchatinov, G. Rüdiger Does Ap stars magnetism result from an instability? (Talk)The kink-type instability of an internal toroidal background field is proposed as a model for the magnetism of Ap stars. The field is produced in young stars by differential rotation. The toroidal field is not detectable but is converted to an observable poloidal field by the instability. The recent observation of a lower magnetic field threshold of about 300 Gauss for Ap stars can be interpreted in terms of the lower limit for the fields producing the instability. Differential stellar rotation suppresses the instability independent of the sign of rotational shear. The instability is nonaxisymmetric with azimuthal wave number m = 1. The unstable disturbances drift in counter-rotation direction. The drift rate increases with field strength so that apparent rotation rates of magnetic patterns tend to decrease for stronger fields. » topACT - "Exoplanets, stellar activity, and the star-planet connection" D. Kitzmann, A.B.C. Patzer, P. v. Paris, M. Godolt, J. L. Grenfell, H. Rauer Effects of clouds on the climate and emission spectra of Earth-like extrasolar planets (Talk)Cloud particles can have an important impact on the climate of planetary atmospheres by either scattering of the incident stellar radiation back to space (albedo effect) or trapping of IR radiation in the atmosphere (greenhouse effect). Clouds do also have a large effect on the emission spectra of planetary atmospheres, by concealing the thermal emission from the surface or dampening of the spectral features of e.g. biomarker molecules. To study these fundamental effects a parametrized cloud description has been developed and coupled with a one-dimensional radiative-convective climate model including the possibility to account for different amounts of cloud coverages and partial overlap of multilayered clouds. The impact of multilayered clouds in dependence of the cloud coverages on the planetary emission spectra, especially on biomarker signatures, is presented for Earth-like planets orbiting different types of central stars. Implications regarding the clouds influence on the position and extension of their habitable zones are discussed. » topCOS - "Recent advances in cosmology" J.S. Klar, J.P. Mücket A detailed view on filaments and sheets of the WHIM (Talk)Numerical simulations predict a considerable fraction of the missing baryons at redshift z ~ 0 resting in the so called warm-hot intergalactic medium (WHIM). The filaments and sheets of the WHIM have high temperatures (105-107 K) and a high degree of ionisation while having only low to intermediate densities. Therefore their reliable detection is a challenging task for today's observational cosmology. The particular physical conditions of the WHIM structures, e.g. density and temperature profiles, velocity fields, are expected to leave their special imprint on spectroscopic observations. In order to get further insight on those conditions, we perform hydrodynamical simulations of the WHIM. Instead of analysing large simulations of cosmological structure formation, we simulate particular well defined structures and study the impact of different physical processes as well as scale dependencies on those. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" B. Kliem, L. M. Green Flux rope formation preceding coronal mass ejection onset (Talk)We analyse the evolution of very clearly sigmoidal solar active regions over periods of several days up to an eruption. Sigmoids' appear S or reverse-S shaped in X-ray and EUV images. The hot emitting plasma results from magnetic reconnection and traces out part of the magnetic topology, especially topological changes, by expanding from the reconnection site along field lines. The evolution of these coronal sources and of their underlying photospheric field suggests - for several cases demonstrates - that a transformation from an arcade to a flux rope configuration occurs prior to eruption in a significant fraction of the considered events, supporting eruption models that adopt the flux rope topology. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" B. Kliem, M. G. Linton Intermittent reconnection downflow enhancements in a simulated flux rope eruption (Poster)Supra-arcade downflows in X-ray and EUV flare emissions and post-eruption inflows in coronagraph data have been interpreted to be signatures of the downward reconnection outflow from a vertical (flare) current sheet. These downflows show an intermittent occurrence pattern, indicating that the reconnection is bursty in time or patchy in space, or both. We present MHD simulations of such reconnection in the realistic configuration of a vertical current sheet formed beneath and driven by an erupting flux rope. The reconnection is found to develop bursty outflows, both upward and downward, with the upward outflows generally showing the stronger variability. While the reconnection starts early in the rise of the flux rope and its peak upward outflow velocity is closely correlated with the rope's rise velocity, the burstiness develops in a clear fashion only as the rope's height has increased from the initial position by about an order of magnitude, so that the current sheet has reached a sufficient vertical extent. The reconnection downflow shows a series of enhancements, each of them starting at a successively greater height from a newly developed magnetic X line. The plasma temporarily accelerated downward in such an enhancement soon turns into a gradual deceleration and then eventually comes to rest on top of previously accelerated plasma. These findings are consistent with the observations of supra-arcade downflows. This work was supported by NASA SR&T Grant NNH06AD58I. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" B. Kliem, S. Rust, N. Seehafer Helicity transport in a simulated CME (Talk)It has been suggested that coronal mass ejections (CMEs) remove the magnetic helicity of active regions from the Sun. Such removal is often regarded to be necessary due to the hemispheric sign preference of the helicity, which inhibits a simple annihilation by reconnection between volumes of opposite chirality. We have monitored the relative magnetic helicity contained in the coronal volume of a simulated flux rope CME, as well as the upward flux of helicity through a horizontal plane in the simulation box. The unstable and erupting flux rope carries away only part of the initial helicity through the open upper boundary of the box; the larger part remains in the volume. We suggest a simple physical explanation for this result. » topACT - "Exoplanets, stellar activity, and the star-planet connection" R. Köhler, Th. Henning, D. Queloz, A. Quirrenbach, and the ESPRI Team Algorithms for micro-arcsecond astrometry with PRIMA at the VLTI (Poster)Astrometric detection of planets requires a precision of 10-30 micro-arcsec (see Poster by R. Launhardt). For an interferometer with a baseline of 100 m, this corresponds to measuring the (differential) optical path difference with a precision of 5-15 nanometers. This can only be achieved with careful calibration of the instrument, including effects that are irrelevant for almost any other scientific application. Furthermore, we have to take into account a number of astrometric effects, e.g. relativistic light deflection caused by the sun and the planets. We will give an overview of the design of the software, and the methods employed to achieve the scientific goal. » topHOT - "Magnetic fields in hot stars" T. Kondic, R. Arlt, G. Rüdiger Decay of the magnetic field in neutron star crusts (Talk) There is observational evidence indicating that the magnetic fields in neutron star crusts decay with age. Ohmic diffusion and the Hall effect both occur in the crusts and can affect the crustal field evolution. The aim of this talk is to investigate how the magnetic field evolves under the influence of these processes. Ohmic diffusion, if acting alone, proceeds too slow to account for the observed decay rates. On the other hand, the Hall effect, which acts on much shorter time-scales, can enhance the field decay due to the density stratification of the crust. In our model, at the very beginning of the neutron star life, differential rotation creates a strong toroidal magnetic field component from the fossil poloidal field. Afterwards, the resulting field is subjected to the magnetic field decay process. The results of the calculations of the magnetic field evolution are presented and the influence of the Hall effect is discussed in detail. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" A. Kopp Magnetic interaction in planetary magnetospheres and extrasolar planetary systems (Talk)Even before the spaceflight era, radio signals from Jupiter revealed not only the fact that other planets are magnetised, too, but also that there is a magnetic interaction between the planet and its innermost Galilean satellite, Io. Today all planets of the Solar System except for Venus and Mars are known to be magnetised, forming magnetospheres as a result of the interaction of the planetary magnetic fields with the Solar wind. As shown, using the example of the weakly magnetised Mercury, the Solar wind with the embedded interplanetary magnetic field can directly interact with the magnetospheres. This interaction can lead to events like substorms known from the magnetosphere of the Earth. The magnetospheres of the gas planets, on the other hand, are dominated rather by internal processes like the rapid rotation of their planets. Moreover, their satellites move around their planets on much smaller orbits, if measured in planetary radii, leading to the above-mentioned possibility of a magnetic interaction between satellite and planet. In addition to a presentation of the magnetospheres of the gas planets, this interaction is exemplified in detail. The search for extrasolar planets has led to the detection of so-called hot Jupiters', giant planets on extremely close orbits around their host stars. In contrast to the planets of the Solar system, some of these stars do magnetically interact with their stars. In the last part it will be shown how these observations can be explained qualitatively and quantitatively by transferring the model of the Jupiter-Io scenario to these systems. » topISM - "Dynamical processes in the interstellar medium" M.G.H. Krause, M. Schartmann, A. Burkert, M. Camenzind Radiation pressure and turbulence near Active Galactic Nuclei (Talk)Kinetic and radiative energy density of the interstellar medium are comparable in the vicinity of strong radiation sources like active galactic nuclei (AGN). I will present a new turbulence toy model that includes the effects of radiation pressure. The model has three main effects: Due to the mutual radiative repulsion of dense clouds, they possess an effective elasticity, reducing dissipation. Second, the small scale forces between clouds / condensations may drive turbulence. Third, the radiation pressure increases the Jeans mass, which may lead to a particular shape of the initial mass function near AGN. » topPLE - "Plenary session" R.P. Kudritzki Dissecting Galaxies with the Brightest Stars in the Universe (Schwarzschild Lecture)Stellar astronomy has reached the stage where the quantitative spectral analysis of individual stars in distant galaxies can provide invaluable information about galaxy evolution. The ideal objects for this purpose are B and A supergiants, which are the intrinsically brightest "normal" stars at visual light. With absolute visual magnitudes up to -9, they are as bright as globular clusters or faint dwarf galaxies. They are ideal to study young stellar populations in galaxies beyond the Local Group to determine chemical composition and evolution, interstellar extinction, reddening laws and distances. The talk will summarize our knowledge of these objects based on high spectral resolution studies in the Milky Way and Local Group. It will then present most recent results on the quantitative spectral analysis of such objects in galaxies beyond the Local Group based on medium and low resolution spectra obtained with the ESO VLT and Keck. We will describe the analysis method, discuss the determination of metallicity and metallicity gradients, and we will introduce a new method to measure accurate extragalactic distances based on the stellar gravities and effective temperatures obtained. Finally, we will discuss the perspectives of future work using the the giant ground-based telescopes of the next generation such as the TMT and the E-ELT. » topACT - "Exoplanets, stellar activity, and the star-planet connection" M. Küker, L.L. Kitchatinov, G. Rüdiger Differential rotation and meridional flows of young stars (Poster)Though not a field generator itself, the meridional flow plays a crucial part in the stellar dynamo process. As differential rotation and meridional flow are closely related, theoretical models of stellar rotation also make predictions about the flow. We compare surface rotation laws from theory with recent observations and discuss the predicted meridional flows and their potential impact on the stellar dynamo. » topHOT - "Magnetic fields in hot stars" B. Kulebi, S. Jordan, F. Euchner, B. Gaensicke, H. Hirsch Analysis of magnetic white dwarfs detected in the SDSS (Talk)We model the structure of the surface magnetic fields of the hydrogen-rich white dwarfs in the SDSS. We used simple centered dipoles or dipoles which were shifted along the dipole axis to model the coadded SDSS fiber spectrum of each object. We have analysed the spectra of all known magnetic DAs from the SDSS (97 previously published plus 44 newly discovered) and also investigated the statistical properties of magnetic field geometries of this sample. The magnetic fields span a range between ~ 1 and 900 MG. Our results further support the claim that Ap/Bp population is insufficient in generating the numbers and field strength distributions of the observed MWDs. Moreover clear indications for non-centered dipoles exist in about ~ 50% of the objects which is consistent with the magnetic field distribution observed in Ap/Bp stars. » topACT - "Exoplanets, stellar activity, and the star-planet connection" J. Langfellner, D. Homeier, S. Dreizler Simulating the Rossiter-McLaughlin effect for transiting planets in eccentric orbits (Poster)Most of today's known transiting extrasolar planets are in nearly circular orbits around their host stars and are thought to be roughly in spin-orbit alignment. However, exceptions have been found, for instance the systems HD 80606 and HAT-P-2, which show a high eccentricity. Using a spectral synthesis code based on the program Bruce' by Richard Townsend, eclipsed spectra and light curves of the host stars were simulated to calculate the residual radial velocity due to the Rossiter-McLaughlin effect for these systems, together with the well studied system HD 209458. Bruce' provides a model of the deformation of the star's surface depending on the effective temperature, the rotation velocity and average surface gravity. The surface is divided in small regions, for each of which a spectrum is calculated for the local atmospheric parameters and radial velocity. These are summed up to form the total emergent (reference) spectrum. If the planetary disk covers a part of the star during the transit, the corresponding regions omitted from the total spectrum at this time. Cross correlation between the reference and the transit spectrum leads to the residual radial velocity. On this poster, the results of the simulations are presented and discussed with regard to observed data. » topACT - "Exoplanets, stellar activity, and the star-planet connection" R. Launhardt, J. Setiawan, Th. Henning, M. Kürster, A. Müller, P. Weise Exoplanets and starspots - the case of TW Hya (Talk)Finding planets around young stars is crucial for our understanding of planet formation. However, their detection is challenging due to the effects of enhanced stellar activity at young ages. We have carried out a systematic radial velocity (RV) survey of nearby T-Tauri stars and developed techniques to disentangle the effects of activity from that of companions. This program has resulted, among others, in the discovery of a giant planet orbiting TW Hya, the nearest classical T-Tauri star that also exhibits a circumstellar disk. The data also show evidence for stellar activity (spots), but smaller amplitude and a different period. However, this discovery has been challenged by others and the question remains under debate whether the data inevitably infer the presence of a planet or can be explained by photospheric activity only. We have critically reanalyzed all data, including new measurements, and discuss the results and arguments. » topACT - "Exoplanets, stellar activity, and the star-planet connection" R. Launhardt, Th. Henning, D. Queloz, A. Quirrenbach, et al. ESPRI - the astrometric exoplanet search with PRIMA (Poster)More than 350 extrasolar planets have been found until today, the vast majority of them with the radial velocity method. Consequently, our knowledge on the properties of extrasolar planetary systems is still heavily affected by the detection biases of this method. However, the dominant role of the radial velocity technique is slowly eroded by the arrival of new facilities. The ongoing developments by European Southern Observatory of the PRIMA dual-feed capability of VLTI will provide us soon with the relevant infrastructure to carry out an astrometric search for planets. This will complement some weakness inherent to the radial velocity method and open new discovery spaces. In order to speed up the full implementation of the astrometric capability of the VLTI and to carry out a large astrometric Exoplanet Search program with PRIma (ESPRI), a consortium lead by the Observatoire de Geneve (Switzerland), the Max Planck Institute for Astronomy, and the Landessternwarte Heidelberg (Germany), has built the Differential Delay Lines (DDLs) for PRIMA and is currently developing the astrometric data reduction software. When equipped with DDLs, PRIMA will be able to perform high-precision narrow-angle astrometry in K-band, reaching a precision of 10-30 μas. It will thus be capable of detecting Saturn and Uranus-mass planets around nearby main sequence stars of any spectral type. Since astrometry does not depend on narrow and stable spectral lines, it will also be sensitive to Jupiter-like planets around young stars. This poster gives an overview of the technical developments and outlines the scientific preparations as well as the goals and prospects of the ESPRI survey, anticipated to start in late 2010, when PRIMA becomes operational. » topELT - "The E-ELT - status, timeline, and instrumentation" U. Laux, J. Greiner, S. Klose A focal reducer system for the E-ELT (Poster, registered after deadline)Telescope time is rather expensive, making it desirable to use all the light collected from a cosmic source and not just the light in a certain filter band. This holds in particular for the E-ELT. Here, we show the preliminary results of a study for the optical design of a focal reducer system for the E-ELT which reduces the aperture ratio from 1:17.7 to approximately 1:3, similar to what was designed for MOSCA, CAFOS, and PMAS on Calar Alto. In combination with dichroic beam splitters up to nine different filter channels are possible, allowing for a simultaneous imaging (or spectroscopy) from approximately 400 nm to 2500 nm. » topHIS - "WG History of Astronomy" D. Lemke 150 Jahre Astrophysik - Kirchhoff und Bunsens Spektroskopie der Sonne in Heidelberg (Talk)Im Jahre 1859 wandten Gustav Kirchhoff und Robert Bunsen die damals neue spektroskopische Methode auf einen Himmelskörper an. Durch gleichzeitiges Beobachten von im Labor erzeugten Spektren verschiedener Stoffe konnten sie mehrere Elemente auf der Sonne nachweisen. Auch die Entstehung der dunklen Linien in einer kühlen Sonnenatmosphäre wurde erklärt, was zu Kirchhoffs Strahlungsgesetz von 1859 führte. Das verwendete 4-Prismen-Spektrometer konnte ein meterlanges Sonnenspektrum zur sicheren Identifizierung der Linien liefern. In Heidelberg sind noch Spuren dieses Beginns der Astrophysik zu finden. » topESC - "eScience: new tools for research in astronomy" G. Lemson German Astrophysical Virtual Observatory (GAVO): Mining the (real and virtual) Universe (Talk)The German Astrophysical Virtual Observatory (GAVO) coordinates the activities of the German astronomical community in the world wide Virtual Observatory (VO) effort and is its national representative to the International Virtual Observatory Alliance (IVOA). The idea of the VO is to investigate how best to disseminate astronomical data and services to the community, and to assist astronomers and astrophysicists worldwide in participating in this effort. In this presentation I will give a short overview of GAVO's activities and results to date. » topACT - "Exoplanets, stellar activity, and the star-planet connection" F. Lenz, A. Reiners Star-planet interactions (Poster)Using Data from the ESO archive and the HET we analyze spectra from HD 209458 and Tau Boo for star-planet interactions. A closely orbiting planet could induce chromospheric activity, due to gravitational or magnetic interaction. Analyzing the Ca ii H & K Lines we search for recurring emission with the same period as P_orb. We present our analysis from archive data of HD 209458, in which we find no signs of periodic Ca ii K Emission, and we show our results from HET data of Tau Boo. » topELT - "The E-ELT - status, timeline, and instrumentation" R. Lenzen, A. Glass, J. Blommaert, B. Brandl, F. Molster, E. Pantin, L. Venema METIS, the E-ELT Mid-Infrared Instrument (Talk)METIS is the Mid-Infrared instrument designed for the E-ELT focus station A1/B1. An international consortium of Duch, German, French, UK and Belgique institutes is currently providing a phase A study of such instrument, that will offer direct imaging and polarimetric observational capabilities as well as low resolution longslit and high resolution IFU spectroscopic modes. An overview of the main science cases will be given. The instrumental concept will be described focussing on some critical components. » topINS - "Innovations in spectroscopy" A. Liermann, W.-R. Hamann, L. M. Oskinova, H. Todt 3D spectroscopy of the Quintuplet cluster with SINFONI (Talk)The Galactic center stellar cluster Quintuplet has been observed with the ESO VLT integral field spectrograph SINFONI-SPIFFI, mapping the cluster center by 22 fields with slight overlaps. We present steps of the data reduction process that are performed to construct a calibrated 3D mosaic data cube. From this cube pass-band images as well as flux-calibrated spectra can be obtained for all detected objects within the field of view. Synthetic aperture photometry and spectra are then employed for the analysis of the massive stars in which the cluster is specially rich. » topCOS - "Recent advances in cosmology" T. Lisker, J. Janz, S. Weinmann Early-type dwarf galaxies as tests of cosmological models? (Talk)The formation of early-type dwarf (dE) galaxies, the most numerous galaxy type in clusters, is commonly believed to be linked to environmental transformation processes. However, several recent studies indicate that a significant fraction of dEs might have formed within the standard paradigm of hierarchical structure formation, like their giant counterparts. We present a comparison of observational data with semi-analytic model predictions, and show that a common formation of giant and dwarf early types appears more plausible than what is frequently stated in the literature. This can be of particular importance for the new generations of cosmological N-body simulations, since they finally reach significantly into the dwarf mass regime. We therefore present ongoing investigations focusing on cluster dwarf galaxies in the Millennium-II simulation, thereby also aiming at deriving predictions for future generations of telescopes, which can probe dwarf galaxies in much larger distances. » topCOS - "Recent advances in cosmology" C. Llinares The Bullet cluster as a test for cosmology (Talk)The discovery of the Bullet cluster had a strong impetus on cosmology. It represents a merging cluster where a clear separation of the dark matter and the X-ray gas could be identified. So while supporting standard LCDM model by giving new evidence of dark matter, the inferred high relative velocities of the two components seem very extreme. I will discuss the abundance of high-velocity mergers in cosmological simulations of the standard and alternative cosmologies. » topGAL - "Galactic archaeology" S. Lucatello, J. Johnson, T. Masseron The nature of C-enhanced, metal poor stars and AGB nucleosynthesis at low [Fe/H] (Talk)The very high fraction of C-enriched stars among the low end of the Galactic halo metallicity distribution along with the wide variety of their neutron capture elements content make the understanding of their formation scenario(s) of extreme interest. The combination of accurate determinations of their chemical composition with long term radial velocity monitoring is crucial to address this issue. I will discuss the results of the long term radial velocity monitoring for C-enhanced metal poor stars and the constraints our findings set on their formation scenarios, exploring the connection between chemical peculiarities and binarity membership and orbital parameters. I will also present abundances for the poorly studied element F, measured from infra-red high-resolution spectra, for sample of 10 C-enhanced metal poor stars with [Fe/H] ranging from ~ eq-1.0 to -3.0. This sample increases by a factor of three the number of F detections in C-rich, metal poor stars and provides the first F measurement in an object with [Fe/H]<-2. The comparison of our results to the prediction of state-of-the-art theoretical models and the implications in our current understanding of Asymptotic Giant Branch nucleosynthesis will be discussed. » topGAL - "Galactic archaeology" J. Ludwig, E. Grebel, T. Lisker Is there a substructure problem in the Virgo cluster? (Poster)In 1999, Moore et al. demonstrated that there is a pronounced missing satellite' or substructure problem in the Local Group, when comparing the number of known Galactic satellites to the number of theoretically predicted dark matter halos. But Moore et al. also indicated that there does not seem to be such a problem in the Virgo cluster. Motivated by this intriguing difference, we revisit the kinematics of Virgo cluster early-type dwarf galaxies, based on a modified Tully-Fisher and Faber-Jackson relation. Turning velocity information into mass estimates, we compare the galaxy distribution with the predictions of numerical simulations. The comparison of the total number density of observed galaxies with that in the simulations shows good agreement for galaxies with rotational velocity larger than v_rot = 150 km/s. The deviation from the numerical simulations increases with decreasing rotation. Hence our more detailed analysis shows that the substructure problem is also seen in the Virgo cluster. » topACT - "Exoplanets, stellar activity, and the star-planet connection" R. Lutz, S. Schuh, R. Silvotti, and the EXOTIME collaboration Photometric monitoring of pulsating subdwarf B stars (Poster)The EXOTIME program is a collaboration of various observers to conduct long-term time-series photometry of selected pulsating horizontal branch objects. Our goal is to search for exoplanets around these evolved stars by studying timing effects and to gain insight on late stage planetary systems. The target list currently includes five pulsating subdwarf B (sdB) stars. Appliying the O-C method, we will also be able to derive evolutionary timescales. Here we will report on our progress in the analysis of the target HS 0702+6043. » topELT - "The E-ELT - status, timeline, and instrumentation" The MICADO consortium MICADO: the adaptive optics imaging camera for the E-ELT (Talk)MICADO is the multi-AO imaging camera for the E-ELT. It has been designed and optimised for use with MCAO, but will have its own SCAO module for the initial operational phase at first light. I will describe the instrument's key capabilities, outline the science drivers, and show how these have shaped its design. The science drivers have led to a number of requirements on the AO system related to astrometry, photometry, and knowledge of the PSF. I will discuss why these requirements have arisen and how we can address them. » topISM - "Dynamical processes in the interstellar medium" P. Marcum, E. Young, E. Becklin, D. Kniffen, A. Krabbe, T. Roellig, and the SOFIA Team Infrared spectroscopic investigations of the solar system, star formation and astrochemistry with the Stratospheric Observatory for Infrared Astronomy (SOFIA) (Talk)The joint U.S. and German Stratospheric Observatory for Infrared Astronomy (SOFIA) will be a premier observatory facility for studying the physics and chemistry of stellar evolution processes, with an operational life spanning multiple decades. Utilizing the large suite of science instruments and broad wavelength coverage of SOFIA, astronomers will be armed with unique capabilities to undertake a large breadth of investigations ranging from studies of the Solar System to the star forming history of galaxies over cosmic time. SOFIA is a German-built 2.5-meter telescope mounted in a modified Boeing 747-SP aircraft supplied by NASA. Flying at altitudes as high as 45,000-feet, SOFIA will be used to conduct spectroscopic and imaging observations throughout the infrared and sub-mm region with an average transmission of greater than 80%. SOFIA's first-generation instrument complement includes broadband imagers, moderate resolution spectrographs capable of resolving broad features due to dust and large molecules, and high resolution spectrometers suitable for kinematic studies of molecular and atomic gas lines at km/s resolution. SOFIA science applications will be discussed, with special emphasis on investigations related to infrared spectroscopy of astrophysical gas, grains and ices. Although the primary impact of SOFIA will be its scientific return, SOFIA's other major advantages include the provision of a platform on which to demonstrate new future technologies and to provide in-flight science training to young scientists, educators and journalists, and its suitability in serving the role as a public ambassador for astronomy. » topELT - "The E-ELT - status, timeline, and instrumentation" J. Melnick, G. Monnet, F. Kerber Building a performance-oriented Site Merit Function for the E-ELT (Talk)Selecting and then ensuring access to an optimum site for the European Extremely Large Telescope (E-ELT) is a crucial step for the project, planned at the end of 2009. One critical factor towards such a choice is the relative scientific efficiency of the various potential E-ELT sites currently being investigated in depth. The talk will address successively the main site observational data, the performance-oriented Site Merit Function built for the E-ELT, and some provisional results. » topINS - "Innovations in spectroscopy" S. Moehler, P. Bristow, F. Kerber, A. Modigliani Quality control for XShooter (Talk)XShooter is the most recent addition to the suite of instruments at the ESO VLT. It is a spectrograph covering the wavelength range from 300 nm to 2500 nm in one shot with the resolution for 1" slit width ranging from 5000 for the UVB and the NIR part to 9000 for the VIS part. As usual for ESO VLT instruments the quality of its data is monitored to ensure the proper functioning of the instrument. This talk will illustrate some of the concepts of quality control for this complex instrument. » topACT - "Exoplanets, stellar activity, and the star-planet connection" M. Mohler, S. Dreizler, A. Reiners, T. Mazeh, I. Ribas Improving the mass-radius relation of low-mass stars (Poster)In recent years efforts to find extrasolar planets steadily increased and still do. For that purpose a huge amount of photometric time-series data was obtained using different survey projects. In case the first analysis ruled out possible involvements of exoplanets, the according data sets were often set aside. These contain many eclipsing binaries with low-mass stellar companions. Several rejected objects of the TrES-survey are now used for mass-radius determinations of several bright eclipsing binaries with low-mass companions. Therefore observations at the Calar Alto Observatory (Spain) with the 2.2 m telescope using the Echelle spectrograph FOCES have been obtained at the end of May 2009. The preliminary results presented on this poster describe the derivation of the radial velocity variations for reliable mass and radius determinations. » topINS - "Innovations in spectroscopy" A. Monreal-Ibero, J. M. Vilchez, C. Muñoz-Tuñon A detailed 2D spectroscopic study of the central region of NGC 5253 (Talk, registered after deadline)Starburst are considered one of the main contributors to the chemical enrichment of the Interstellar Medium. However, the mechanisms that govern the interaction between the recent/on-going star formation and the surrounding gas are not yet fully understood. Because of their \empha priori simplicity, the subgroup of H ii galaxies constitute the ideal environment to study these mechanisms. Here, we present a detailed study of the central region of a nearby H ii galaxy, NGC 5253, using optical Integral Field Spectroscopy with FLAMES at the VLT. In particular, the extinction and electronic density structure will be shown. Also, we will explore the mechanisms reponsible of the ionization in this area. Finally, we will localize the zones showing nitrogen pollution as well as Wolf-Rayet and nebular He ii features. » topINS - "Innovations in spectroscopy" A. Monreal-Ibero, M. Relano, J.M. Vilchez, R. Kennicutt IFS observations of the H ii region NGC 595 (Poster, registered after deadline)Emission line spectra of H ii regions are normally obtained to characterize their physical properties, to extract information of the stellar populations that ionize them, as well as to study the variation of the physical properties of the star forming regions across the galaxy disk. However, the derived physical properties are generally obtained from long-slit spectroscopic measurements centred on the most intense knots, and are not necessarily representative of the conditions in all the locations within the regions. Integral Field Spectroscopy (IFS), covering a continuous field of view, overcomes the limitations of the long-slit observations and allows the study of the variation of the principal emission line ratio across the surface of the object. We present here IFS observations of NGC 595, the second most luminous H ii region in M 33. We compare the Balmer extinction map for the region with observations at 24 μm and 8 μm from Spitzer Space Telescope tracing the emission of the dust within the region. We study the variation of the most used emission line ratios proposed as metallicity callibrators and we show the capability of the IFS to study the existence of Wolf-Rayet (WR) stars, identifying the previously catalogued WRs and detecting a new candidate towards the north of the region. » topCOS - "Recent advances in cosmology" M. Morikawa Formation of autonomous nonlinear structures in the Universe (Talk)Structure formation and their properties in the universe have been mainly studied from the dynamical aspect based on the linear perturbation method supplemented by numerical N-body simulations. We would like to emphasize another important aspect the autonomous structure formation. We propose that the collision-less dark matter fluid turns into a turbulent state, i.e. dark turbulence, after crossing the caustic surface in the non-linear stage. After deriving Kolmogorov scaling laws from the Gravitational-Navier-Stokes equation by the method similar to the one for Smoluchowski coagulation equation, we apply this to scale-dependent velocity dispersion, mass-luminosity ratio, magnetic fields, and mass-angular momentum relation, power spectrum of density fluctuations. They all point the concordant value for the constant energy flow per mass: 0.3 cm2/sec3, which may be understood as the speed of the hierarchical coalescence process in the cosmic structure formation. (astro-ph > arXiv:0805.0172) We further compare these results with the other methods such the infinite summation of graphs, the method of non-additive statistical mechanics, and the local virial relations. » topISM - "Dynamical processes in the interstellar medium" H.S.P. Müller, A. Coutens, A. Walters, J.-U. Grabow, A. Belloche, K.M. Menten, S. Schlemmer The laboratory rotational spectrum of iso-propyl cyanide and an astronomical search in Sagittarius B2(N) (Poster)We have carried out a molecular line survey of Sagittarius B2(N) in the 3 mm region with additional selected recordings at 2 and 1.3 mm to probe the chemical complexity in massive star-forming regions. Noteworthy results include the detection of aminoacetonitrile (A. Belloche et al. 2008, A&A, 482, 179; Erratum 2008, 492 796) which is thought to be a possible precursor of the aminoacid glycine, and the detection of ethyl formate as well as normal-propyl cyanide (A. Belloche et al. 2009, A&A, 499, 215) which are among the most complex molecules detected in the interstellar medium thus far. The heavy atoms in the latter molecule form a chain. An isomer with a branched structure, iso-propyl cyanide, also exists, but its rotational spectrum had been recorded only in few microwave transitions up to 40 GHz. Therefore, laboratory measurements were extended. Measurements in Köln were carried out in selected regions between 40 and 600 GHz. The molecule possesses a strong a-dipole moment component and a smaller c-component. Since the c-type transitions appeared to be weaker than predicted additional Stark (and also zero-field) measurements have been carried out in Hannover between 6 and 20 GHz. We will present results of these laboratory spectroscopic investigations as well as the outcome of a search for the molecule in our Sgr B2(N) line survey. The ratio of the two isomers, even a sufficiently low upper limit for iso-propyl cyanide, should provide important clues on the interstellar chemistry leading to complex molecules. » topISM - "Dynamical processes in the interstellar medium" H.S.P. Müller, J. Stutzki, S. Schlemmer The Cologne Database for Molecular Spectroscopy, CDMS, a tool for deciphering the Universe through spectroscopy (Talk)The CDMS provides in its catalog section atomic and molecular line lists for species that have been or may be observed in space by radio astronomical means. It is available online at http://www.astro.uni-koeln.de/cdms/ and has been described in H. S. P. Müller et al., A&A, 2001, 370, L49 and J. Mol. Struct., 2005, 742, 215. The line list of each molecule is gathered in an individual entry; minor isotopologs have separate entries, and the same applies to excited vibrational states with the exception of some diatomic molecules. With 5 to 10 new or updated entries each month, the CDMS catalog has been growing rapidly over the past 10 years: more than 500 entries have been available in the CDMS since February 2009 - with many more entries to be created. Entries are generated from fitting (mostly) laboratory data to accepted Hamiltonian models. Despite many dedicated laboratory spectroscopic investigations in recent years, accurate data is still lacking frequently - in particular at higher frequencies, for minor isotopic species, for excited vibrational states, or for somewhat larger molecules. Using recent results, we will show that these issues are already important for single dish observations and even more so for ALMA or other radiotelescope arrays. Moreover, they do not only matter in molecular line surveys or in searches for more complex molecules, but also e.g. for observations of red-shifted CO. The main features of the CDMS catalog will be described, including recent developments concerning new entries as well as available and planned features. Attention will be given to laboratory spectroscopic needs for the far-infrared missions Herschel and SOFIA as well as for telescope arrays such as ALMA, the EVLA, and the SMA both, in terms of general aspects and in terms of specific examples. % maybe also Spliter ESC ? also welcome as poster » topMSC - Plenary session (posters only) S. Müller, S. Geier, U. Heber The cool companion of AA Dor - brown dwarf or late M star? (Poster)We performed a quantitative analysis of UVES data and determined the projected rotational velocity as well as effective temperature and surface gravity. We conclude that AA Dor is most likely a helium core burning sdB rather than a post-RGB object and that the companion is a late M dwarf. » topHOT - "Magnetic fields in hot stars" Y. Naze Magnetic stars: which diagnostics in X-rays? (Talk)Magnetic fields of hot stars have been a rather elusive subject until spectropolarimetric measurements enabled some clear detections a few years ago. At the same time, X-ray observatories with a high sensitivity and a high resolution were observing hot stars, and a link between peculiar X-ray features and the presence of magnetic fields was soon proposed. I'll review the high-energy observations of such objects, the questions that they raised, and the pending issues. » topHOT - "Magnetic fields in hot stars" Y. Naze, N. Walborn, F. Martins, G. Rauw The strange case of the Of?p stars (Poster)The Of?p classification applies to Of stars with unusually strong C iii emission. To better understand these objects, we have undertaken a dedicated multiwavelength monitoring. It has unveiled the peculiar characteristics of these strange stars: varying line profiles, photometric changes, and X-ray overluminosity (and in some cases clear phase-locked variations). The physical interpretation of these properties remains problematic. » topMSC - Plenary session (posters only) A. Nesis, R. Hammer, H. Schleicher, M. Roth 2D spectroscopy of velocity fields in the solar photosphere (Poster)We analyzed 2D spectroscopic observations of the quiet solar disk center, obtained with the Triple Etalon Solar Spectrometer (TESOS), supported by the adaptive optics system at the Vacuum Tower Telescope at the Teide observatory on Tenerife. The observations include both white light images and simultaneously taken scans through the nonmagnetic line Fe i 5576.6 nm. The 2D coherence between the non-oscillatory velocity fields formed at the continuum layer and at the highest layers probed by this line drops to 0.7. The 2D observations enable us to study topological properties of the velocity field, which reflect the hydrodynamic properties of the plasma, such as the increase of anisotropy with height over the observed field of view. This effect is not only evident from visual inspection, but is also analyzed quantitatively. » topACT - "Exoplanets, stellar activity, and the star-planet connection" R. Neuhäuser, A. Koeltzsch, St. Raetz, M. Mugrauer Activity cycles around young stars? (Talk)With BVRI band photometric data spanning almost 50 years (1960s until 2009), we have reinvestigated the variability of the young, naked, weak-line, run-away T Tauri star Par 1724 just north of the Orion Trapezium. We used archival and published data, new own observations from 0.9-m Dutch telescope on la Silla, the 0.9-m Wendelstein telescope of University Munich, a 25-cm telescope of the University Observatory of Jena, as well as from the ASAS automatic sky survey. The previously known 5.7 day rotation period was confirmed. In addition, evidence for a 9- or 17.5-year cycle was found in both V-band magnitudes and variability amplitude. This would be the youngest star found so far with a cycle. If due to a dynamo, one would expect a small degree of differential rotation, e.g. two apparent rotation periods with a difference of only a fraction of a day. Most recently, we have searched for such a signal in the data and will report the results. In addition, we have started to search for cycles also around other young stars, partly also using archival plates. We will also briefly mention other observing programs at the University Observatory Jena, in particular regarding the activity of stars and the search for exo-planets by transits and transit time and duration variations. » topMSC - Plenary session (posters only) R. Neuhäuser, S. Minardi, L. Ramirez, A. Chipouline, S. Kraemer, T. Pertsch, M. Vanko, T. Pribulla, G. Maciejewski (FSU Jena), B. Stecklum (TLS) Photonic solutions for high performance laser metrology of an astronomical interferometer (Poster)Besides atmospheric turbulence, mechanical vibrations of optical components can seriously affect the fringe contrast in astronomical interferometers. Usually the frequencies of the mechanical resonances fall outside the detection bandwidth of conventional fringe trackers and therefore require dedicated metrology. Here we present our most recent achievements in the development of a fiber interferometer which could be used to measure the displacement of vibrating mirrors in a broad frequency range and with an accuracy better than 10 nm. We also discuss a few possible astronomical applications, including vibration measurement metrology for the VLT UTs. » topESC - "eScience: new tools for research in astronomy" I. Nickelt, M. Demleitner Digitising Astronomical Historical Data (Talk)We use the GAVO Data Center to publish historic photographic plates, observed almost a hundred years ago as part of the "Carte du Ciel" project. We describe the process of digitisation of data and metadata and the different steps to achieve a VO compatible publication, starting with simple fits files and ending with cone search dicovery and retrieval by VO tools. » topINS - "Innovations in spectroscopy" H. Nicklas, C. Köhler, H. Anwand, A. Fleischmann, et al. 2nd generation VLT-instrument MUSE - instrument hardware (Talk)After passing the Final Design Review of ESO, the instrumental design at the beginning of the manufacturing phase will be presented. It will address the main central structure, the link to the VLT unit telescope, the different subsystems as well as the 24 units for integral field spectroscopy. » topGAL - "Galactic archaeology" A.M. Nicuesa Guelbenzu, W.W. Zeilinger Origing of the ionised gas in a sample of early-type galaxies (Poster)The properties of the warm gas are studied in a sample of nearby early-type galaxies. A progress report is given on the analysis of optical long-slit spectra and NIR imaging. The emission lines are analysed to study ionisation mechanisms in the nuclear and extra-nuclear regions. Gas abundances are derived and compared with metallicities obtained from absorption lines in order to study the possible ionisation mechanism of the warm gas. We investigate the kinematical properties of the ionised gas (velocity dispersions and radial velocity profiles) to study the relation with the stellar populations of the host galaxy. The comparison of the colour in the NIR bands with the predictions of population synthesis models permits us to constrain ages and metallicities of the stellar population. » topCOS - "Recent advances in cosmology" M. Nord, K. Basu, F. Pacaud, P. A. R. Ade, A. N. Bender, B. A. Benson, F. Bertoldi, et al. De-projecting the physical structure of the intra-cluster medium using the Sunyaev-Zel'dovich effect (Talk)Accurate modeling of the mass of galaxy clusters is crucial for their use as cosmological probes, and independent measures of the mass-observable scaling relations from observations of galaxy clusters at different frequencies are important to understand the systematic bias in each method. The observation of the thermal Sunyaev-Zel'dovich Effect (tSZE) is considered a powerful complement to X-ray observations for modeling the physical properties of the intra-cluster gas (ICM). We present first results of resolved bolometer array imaging of rich galaxy clusters with the APEX telescope. The sensitivity and the spatial dynamic range of the APEX-SZ instrument allows a non-parametric de-projection of the ICM properties in conjunction with X-ray data, and the validity of the hydrostatic equilibrium assumption that has been used to estimate the total cluster mass can thereby be tested. » topACT - "Exoplanets, stellar activity, and the star-planet connection" L. Nortmann, S. Dreizler, A. Reiners Observations of low-mass and planet host stars with the MONET-Telescope (Poster)The Institute for Astrophysics Göttingen operates two robotic 1.2 m telescopes at McDonald Observatory and at the South African Astronomical Observatory. This allows us to conduct long-term monitoring to search for stellar variability of all kinds. In this project, we engage in photometric observations of two potential planet host stars of class M, which are simultaneously investigated in an ESO Large Program searching for radial velocity variations of low mass stars. Here we report first results on stellar activity of these targets. Furthermore we present data from a photometric follow-up transit observation of an established planet host star. » topCOS - "Recent advances in cosmology" Kourosh Nozari On the phantom-like prescription without phantom matter (Poster)We investigate possible realization of the phantom-like behavior in the framework of f(R)-gravity models where there are no phantom fields in the matter sector of the theory. By adopting some observationally reliable ansatz for f(R), we show that it is possible to realize phantom-like behavior in f(R)-gravity without introduction of phantom fields that suffer from instabilities and violation of the null energy condition. Depending on the choice of f(R), the null energy condition is fulfilled in some subspaces of each model parameter space. We extend this model to a DGP-inspired braneworld model where induced gravity on the brane is modified in the spirit of f(R) gravity and stringy effects are taken into account by incorporation of the Gauss-Bonnet term in the bulk action. We show that this scenario is a successful alternative for dark energy proposal. The effective equation of state parameter of the model crosses the cosmological constant line naturally and smoothly in the same way as observational data suggest. » topGAL - "Galactic archaeology" P. Ocvirk The interplay between observations and theory in integrated light spectroscopy of galaxies: when blue horizontal branch stars maskerade as young stars (Talk)Model color magnitude diagrams of low-metallicity globular clusters usually show a deficit of hot evolved stars with respect to observations. We investigate quantitatively the impact of such modelling inaccuracies on the significance of star formation history reconstructions obtained from integrated spectra. To do so, we analyse the sample of spectra of galactic globular clusters of Schiavon et al. with STECKMAP (Ocvirk et al.) and the stellar population models Vazdekis et al. and Bruzual & Charlot, and focus on the reconstructed stellar age distributions. We then identify a confusion zone' where fake young bursts of star formation pop up in the star formation history although the observed population is genuinely old. These artifacts appear for 70-100% of cases depending on the population model used, and contribute up to 12% of the light in the visible. Their correlation with the horizontal branch ratio indicates that the confusion is driven by HB morphology: red horizontal branch clusters are well fitted by old stellar population models while those with a blue HB require an additional hot component. As a consequence, any young starburst superimposed on an old stellar population in this metallicity range could be regarded as a modeling artifact, if it weights less than 12% of the visible light, and if no emission lines typical of an H ii region are present. » topGAL - "Galactic archaeology" P. Ocvirk, R. Peletier, A. Lancon Extragalactic archeology in integrated light (Talk)Detailed kinematics as obtained from spectroscopy of resolved stars in the Milky Way or local group galaxies, are extremely valuable to study the formation of galaxies. Here we attempt to recover the kinematics with similar detail, but for more distant galaxies, and hence in integrated light. To do so, we model the spectrum of galaxies as a sum of several stellar components, each with individual age and kinematics. This results in reconstructing an age-velocity diagram. I will show the outcome of applying this technique to NGC 4030. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" H. Önel, G. Mann Electron acceleration in a flare plasma via coronal circuits (Talk)A major aspect for investigation of the electron acceleration in the corona is to understand the origin of the electric fields that lead to the electron acceleration. In this presentation a mechanism is presented to generate a large scale DC field that subsequently can perform the electron acceleration. The generation of the electric field is investigated with electric circuits. Afterwards the electric field is used to calculate electron spectra which can be compared with X-ray spectra obtained by RHESSI spacecraft. » topACT - "Exoplanets, stellar activity, and the star-planet connection" P.v. Paris, M. Godolt, J.L. Grenfell, P. Hedelt, B. Patzer, H. Rauer, B. Stracke Extrasolar planets in the Gliese 581 system - model atmospheres and implications for habitability (Poster)The planetary system around the M dwarf Gliese 581 contains at least four planets, three of them are considered Super-Earths with masses between two and seven times the mass of the Earth. The planets Gliese 581 c and d were the first planets which merited a detailed study of their potential habitability. The first published studies concluded that Gliese 581 c was too hot for habitable conditions, whereas Gliese 581 d was located just beyond the outer edge of the habitable zone. However, the orbital distances of the two planets have recently been revised based on a longer radial velocity baseline, putting them about 10% closer to the star (Mayor et al. 2009, submitted to Astronomy & Astrophysics). In order to investigate the habitability of Gliese 581 c and d under these new conditions, we applied a 1D radiative-convective model to potential atmospheric scenarios by varying the surface pressure and atmospheric composition. » topCOS - "Recent advances in cosmology" A. Partl, A. Dall'Aglio, V. Müller, G. Hensler Cosmological radiative transfer for the line-of-sight proximity effect (Poster) We investigate the signature of the proximity effect near high redshift quasars employing 3D radiative transfer simulations in the framework of hierarchical structure formation. By selecting 3 different quasar environments at redshift 3, 4 and 4.9 we model the radiative influence of the cosmic UV background radiation field and a luminous quasar. We analyze a set of 500 synthetic sight lines at each redshift and environments considered here to determine the proximity effect strength along individual spectra. By constructing the proximity effect strength distribution (PESD) we find that the cosmic density field fluctuations are responsible for the large dispersion in the proximity effect strength along different sight lines. The PESDs are further affected when considering different SEDs for the quasar or the UVB. » topCOS - "Recent advances in cosmology" A. Partl, V. Müller Large scale structure bias of the proximity effect (Talk)UV photons from quasars enhance the hydrogen photoionization rate in its surrouding and dominate over the diffuse UV background. This phenomenon becomes visible as a suppression of the Lyman alpha forest near to the QSO, known as the line of sight proximity effect. For a given quasar luminosity, the strength of the proximity effect can be used to estimate the ionizing UV background flux. Observations show a large scatter of the proximity effect and tend to overestimate the UV background as compared with flux transmission statistics. We perform detailed radiation transfer and semianalytical simulations to model the proximity effect. While radiation transport effects only marginally influence the quasar surrounding, the large scale density field around the quasar causes a large scatter between different sight lines. Density variations on comoving scales up to 20 Mpc/h tend to bias observational estimates of the proximity effect strength. The bias increases with decreasing redshift and decreasing quasar luminosity. » topISM - "Dynamical processes in the interstellar medium" A.B.C. Patzer, J.W. Stock, Ch. Chang, M. Wendt Nucleation studies of TiC under the conditions of carbon-rich AGB star envelopes (Talk)Dust particles play a central role in the astrophysics of the interstellar medium (ISM) - from chemistry and thermodynamics of the gas up to the dynamics of star formation. The lifecycle of the interstellar dust starts with the nucleation and growth of grains at high densities but relatively low temperatures in steady winds or explosive ejecta of stars. Asymptotic giant branch (AGB) stars and type-II supernovae (SNs) are particularly rich in detected dust compounds. However, most studies of especially dust nucleation in winds of carbon-rich AGB stars consider primarily pure carbon as dust forming material. But dust grains formed in such circumstellar envelopes are rather a mixture of several chemical elements such as titanium or silicon in addition to the main component carbon as verified by many investigations of meteorites. In this contribution we focus on the study of the nucleation of titaniumcarbide. Therefore, the necessary properties of molecular titaniumcarbide clusters are estimated within density functional approaches and their chemical abundances are calculated for conditions being representative for circumstellar dust shells around carbon-rich AGB stars. We present first results on the homogeneous nucleation of TiC and discuss further extensions and perspectives. » topACT - "Exoplanets, stellar activity, and the star-planet connection" F. Pepe, P. Figueira, C. Lovis, M. Mayor, D. Ségransan, D. Queloz, S. Udry Extrasolar planets search and characterization (Talk)Since the discovery of 51 Peg b the search of extra-solar planets has evolved significantly. On the one hand, the number of known exoplanets increases continuously and reaches a level from which statistical properties can be derived. On the other hand, various techniques allow us more and more to also access physical parameters and the atmospheric characteristics of these planets. In my talk I will give an overview of the activities carried out at the Geneva Observatory and try to provide a (certainly incomplete) summary of the current status of the extra-solar planets field. » topCOS - "Recent advances in cosmology" W. Percival Cosmological large-scale structure observations (Talk)I will discuss what observations of galaxy clustering can tell us about cosmology, through Baryon Acoustic Oscillations and redshift-space distortions. Recent results from the SDSS will be presented, and I will conclude by looking ahead to future observations. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" J. Petrasch, L. Schlieder, T. Stein Improved determination of minor planet positions (Poster, registered after deadline)This poster deals with modifications to the Plate Constants Method, a procedure determining the position of small bodies in the solar system such as minor planets. The determinations are done using reference star positions from star catalogues. Since as many stars as possible were used, errors will be minimised through averaging of individual star errors. In the presented work new methods will use less reference stars, as they were developed to identify stars with high error values and to exclude them from further fitting iterations. The implementation of those new derived methods into a self-written software, SAMS, finally ruled out a forecasted improvement via simulations. Later, the results of those simulations were compared to real observational data. The analysis of the data shows strong evidence of such improvement varying from a few to a maximum of some 40 percent, strongly depending on the initial reference star number. With an improvement of obtained positional data we can afford a maximum of data usage and, furthermore, more precise determination of an asteroid's impact threat can be provided. » topGAL - "Galactic archaeology" M. Petrov, G. Hensler Chemo-dynamical evolution of subhalo systems and its effect on the Galactic halo chemistry (Talk)From the hierarchical merging paradigm of structure formation and due to the satellite accretion scenario it can simply be concluded that the galactic halo stars are the relicts of already disrupted and incorporated satellite galaxies of the Milky Way and should therefore reveal abundance similarities with the present-day dwarf spheroidal galaxies. Although several studies support this possibility from the agreement of modelled and observed metallicity distribution of halo stars, the major challenge are the deviating abundance ratios in the dSphs, in particular, their low O/Fe. In reality, however, the halo stars should dominantly be formed during the very early formation epoch and thus cannot be compared to the present-day existing dSphs because the conditions of the accreted population of subhalos should have been different from those having survived. By means of chemo-dynamical simulations of satellite galaxy systems around forming host galaxies taken from CDM cosmological simulations we explore their star-formation history, gain and loss of gas, and their stellar abundance evolution in the early universe until their accretion into the massive galaxy. Since the evolution of each individual satellite is determined by its mass but also its environmental conditions like tidal field of the host, the orbit and proximity of the satellite, etc., we explore the differences of the early accreted satellite population to simplified parametrised correlations of baryonic mass and star-formation rates with the masses of the DM subhalos. » topISM - "Dynamical processes in the interstellar medium" I. Philipp, D. Breitschwerdt, M. Dahlem, C. Brogan, V. Heesen, R.J. Dettmar Cosmic ray electron transport in disks and halos of star forming galaxies (Poster)Cosmic ray (CR) electrons are an essential component of the primary cosmic radiation. Although they constitute only a few percent of the CRs - they provide most of the information we have regarding the interstellar CR propagation and confinement in galaxies and clusters. The understanding of their production and their interaction with magnetic and radiation fields is thus of fundamental importance. Therefore, we have calculated analytically a series of one-dimensional, stationary CR electron transport models based on diffusion and advection in order to get insight into the relations between the quantities involved. These are compared to high resolution multifrequency radio continuum observations of the actively star forming edge-on spiral galaxies NGC 891 (VLA) and NGC 253 (VLA & Effelsberg) obtained by us. These studies provide constraints on the main parameters of the CR electron propagation. Our results favour advection of CR electrons as the dominant transport process in the halos of actively star forming galaxies with diffusion dominating in the disk and lower halo. For the first time transport models including both, diffusion and advection, have been used to interpret radio spectral index distributions with high angular resolution. » topMSC - Plenary session (posters only) S. Pirner, K. Pottschmidt, M. Boeck, M. Hanke, J. Wilms, V. Grinberg, M. Nowak, G. Pooley, S. Markoff Long-term timing analysis of the accreting black hole binary Cygnus X-1 (Poster, registered after deadline)The accreting X-ray binary Cygnus X-1 has been target of our biweekly monitoring campaign with the Rossi X-Ray Timing Explorer (\textslRXTE) for more than ten years. We present the long-term timing analysis of Cygnus X-1 in the 2-70 keV band based on this database with more than 1200 spectra and lightcurves with 2 ms time resolution. The monitoring covers the changes in this accreting system in unprecedented detail. Power spectra (PSD) are calculated for every \textslRXTE orbit ( ~ 90 min). In the spectral hard state, in which Cygnus X-1 is found most of the time, the power spectra in the 0.003-128 Hz range can be described with two to four broad Lorentzian noise components. The peak frequency and strength of these broad-noise components are strongly correlated with the spectral parameters of the source and therefore likely associated with the accretion disk corona. After a transition to the soft state in which the X-ray spectrum is dominated by thermal radiation from the accretion disk, the shape of the power spectrum changes and the broad noise components vanish. The increase of the time lags between light curves at higher and lower energies from the hard towards the transition is a further indicator of the changes in the accretion geometry. Simultaneous radio monitoring with the Ryle Telescope reveals correlations between radio and X-ray emission processes. » topISM - "Dynamical processes in the interstellar medium" S. Plöckinger, G. Hensler Head Tail High Velocity Clouds: a possibility to test the theory of dark matter subhaloes. (Poster, registered after deadline)Assuming an extragalactic origin for the ensemble of compact high velocity clouds (CHVCs) and an amount of dark matter arising from cosmological Λ-CDM theory, the CHVCs should be embedded in dark matter subhaloes when entering the galactic gravitational potential. The baryonic matter interact with the hot halo gas and face ram pressure stripping as well as a deceleration relative to the motion of its own dark matter potential which is not affected by drag force. Based on a stable selfgravitating gas sphere in both hydrodynamic and thermal equilibrium (several heating and cooling processes are considered) surrounded by a hot ambient medium, this work shows how different additional gravitational potentials influence the effect of ram pressure stripping. This setup models the infall of observed CHVCs with a head-tail structure using hydrodynamic FLASH Code 2.5 (Univ. Chicago). » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" M. Pohl Pick-up ions: from the heliosphere to AGNs (Talk)Pick-up ions in the heliosphere are an ideal test medium for the study of kinetic instabilities in collisionless space plasmas, that are triggered by highly anisotropic distribution functions. Similar instabilities play an important role in astrophysical sources such as supernova remnants or active galactic nuclei (AGN), where they not only help in the acceleration of relativistic particles, but may even lead to magnetic-field amplification. The talk will give an overview of current trends in the field. Emphasis will be placed on the relative importance of resonant and non-resonant interactions, and also on large-scale modelling of sources based on new understanding of the small-scale physics. » topACT - "Exoplanets, stellar activity, and the star-planet connection" A. Quirrenbach and the CARMENES Team CARMENES: Study of a radial-velocity spectrograph for Calar Alto (Talk)CARMENES is an ongoing study for a high-precision radial-velocity spectrograph for the 3.5 m telescope on Calar Alto. The main scientific goals of CARMENES are planet surveys of ~ 300 M dwarfs and ~ 3000 K giants. For the M dwarf survey, the brightest objects of mid-M spectral type accessible from Calar Alto will be selected. Their radial velocities will be monitored in the near-infrared (Y, J, and H bands) with a fiber-fed cross-dispersed echelle spectrograph (R ~ 85,000), calibrated with the simultaneous ThAr method. A visible-light spectrograph covering the spectral range from ~ 5,000 to 9,000 Angstroms will provide simultaneous monitoring of variability indicators (mainly H alpha and the Ca ii triplet). In each field, ~ 10 K giants will be selected for simultaneous observations with a multi-object spectrograph covering the wavelength range from ~ 5,000 to ~ 6,000 and stabilized with an iodine cell. » topMSC - Plenary session (posters only) J. Ramirez, S. Komossa Chandra LETGS observation of the variable NLS1 galaxy Ark 564 (Poster)We present an analysis of a 100 ks X-ray spectrum of the Narrow-Line Seyfert 1 Galaxy Ark 564, which we have taken with the Low Energy Transmission Grating Spectrometer (LETGS) on board the X-ray telescope Chandra. We fit several spectral continuum models to the time-averaged X-ray spectrum of this galaxy, and study in detail the possible origin of the observed soft X-ray excess. Also, we characterize the average intrinsic absorption of the system, with the use of self-consistent photoionization modeling. We find that the 0.1-10 keV spectrum can be well described by a power-law plus two thermal components to account for the soft excess. We detect and measure several narrow absorption lines coming from highly ionized species of C, N, O and Fe. The material seems to have a velocity consistent with the systemic velocity of the galaxy. All these results put remarkable constraints on the physical parameters of the absorbing material, spatial location, accretion and outflow mass rates, with important implications for the evolution of the system and the general picture of the AGN unification theory. » topACT - "Exoplanets, stellar activity, and the star-planet connection" Th. Ratzka, S. Wolf, B. Lopez, and the MATISSE consortium Imaging protoplanetary discs with MATISSE (Poster)MATISSE, the Multi Aperture Mid-Infrared SpectroScopic Experiment, is one of the second generation instruments of the VLT Interferometer. Designed to combine up to four telescopes and operated simultaneously in the N- and the L- or M-band, MATISSE allows the efficient interferometric reconstruction of mid-infrared images. It further offers spectral resolutions of up to 1500. MATISSE is thus a unique tool to investigate the distribution and composition of warm gas and dust around a variety of astronomical objects. Moreover, the mid-infrared images will help to bridge the gap between the images taken at shorter wavelengths with adaptive optics systems at the new ELTs and the millimetre maps provided by ALMA. One of the primary science goals of MATISSE is the study of protoplanetary discs to reveal the evolution of the circumstellar material. Even direct signatures of planets like gaps or planetary accretion discs can be detected with MATISSE, because the contrast between the star and the circumstellar environment is already favourable in the mid-infrared. » topACT - "Exoplanets, stellar activity, and the star-planet connection" H. Rauer and the CEST Team The growing CoRoT planetary family (Talk)The CoRoT satellite was launched on December 2006 with two goals: to search for extrasolar planets and study the interior structure of stars. So far, six planets and a brown dwarf (with 20 Jupiter masses) have been reported and several results on stellar seismology are published. Among the highlights of planet discoveries from CoRoT is a small terrestrial planet, CoRoT-7b, with less than two Earth radii size. The present status of the CoRoT mission, with emphasis on the steadily growing CoRoT planet family, will be reported. In addition, potential observational biases of the two currently most successful planet detection methods, radial velocity and transit search, will be addressed. Finally, an outlook to proposed future transit detection missions (PLATO) and prospects for characterization of transiting terrestrial planets will be given. » topISM - "Dynamical processes in the interstellar medium" S. Recchi, G. Hensler Dwarf Galaxies with outflows and gas infall and their effects on element abundances (Talk, registered after deadline)Galactic winds in dwarf galaxies are driven by the energy released by supernova explosions and stellar winds following an intense episode of star formation, which create an over-pressured cavity of hot gas. As observed e.g. in NGC 1569, the X-ray gas is reasonably carrying out gas metal-rich in excess to the normal interstellar medium. In contrast to simplistic models of galactic winds that easily produce a large amount of metal loss in low-mass galaxies and, by this, reduce the metallicity in the galaxy significantly, we can demonstrate that in more refined models not only the mass and shape of the gas determines the strength of the galactic wind but also the external pressure and the multi-phase nature of the ISM. In addition, an external gas reservoir can allow for the infall of gas clouds which again affects the outflow. Here we address the following questions: (i) To what amount sequential star-formation episodes and the multi-phase ISM, in particular embedded gas clouds, also stemming from gas infall, affect the superbubbles outbreak and the galactic wind strength? (ii) How such physical state determines the late evolution of superbubbles and the final fate of the superbubble cavities? (iii) How much does the galactic geometry, like e.g. the flattening of the gas affects the strength of galactic winds? » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" A. Recuenco-Munoz, A. Tritschler, H. Balthasar, K. Strassmeier, C. Denker Two-dimensional spectropolarimetry of an emerging flux region (Poster)Emerging flux regions are small-scale, bi-polar sources of magnetic flux, which can eventually evolve to become pores, sunspots and even complex active regions. Two-dimensional spectropolarimetry was employed to study an emerging flux region in the photosphere (Fe i λ 630.2 nm) and chromosphere (Ca ii λ 854.2 nm and Hα λ 656.3 nm). These data were obtained with the Interferometric Bidimensional Spectrometer\/ (IBIS) at the Dunn Solar Telescope of the National Solar Observatory/Sacramento Peak, New Mexico on May 26, 2008. In addition, speckle reconstructed G-band (λ 430.5 nm) images were used as input to local correlation tracking techniques to provide access to the horizontal photospheric proper motions. This comprehensive data set provides detailed information on flow and magnetic field vectors encountered in small-scale emerging flux regions. » topACT - "Exoplanets, stellar activity, and the star-planet connection" A. Reiners Detecting planets around active low-mass stars (Talk)In this talk I will give an overview of the connection between stellar activity and the quest for planets. Stellar activity can produce starspots that are known on the Sun, in other stars they are inferred from photometry and Doppler imaging. The surface features can cause large radial velocity variations that could mimick a planet's signal, and stellar activity could also be caused by star-planet interactions. Low-mass (M-type) stars can be particularly rapid rotators and very active, and I will discuss the perspectives detecting planets around them. » topHOT - "Magnetic fields in hot stars" K. Reinsch Magnetic fields of white dwarfs (Talk)Magnetic fields have been detected in a significant fraction of white dwarfs. Detailed studies of a few single and accreting white dwarfs have revealed a high degree of complexity of their field structures. I will review the observational progress in the diagnosis and analysis of white dwarf magnetic fields and the theoretical challenges in understanding their structure, origin and evolution. » topINS - "Innovations in spectroscopy" M. Rengel, H. Sagawa, P. Hartogh H2O, HCN, and CO in Titan's atmosphere - a challenge for Herschel (Talk)Herschel was successfully launched on 14 May 2009. In the framework of the guaranteed time key project called Water and related chemistry in the Solar System'*, Herschel will deliver a wealth of line observations of atmospheric gases of Titan, among other objects in the solar system, using all three Herschel instruments (Heterodyne Instrument for the Far Infrared (HIFI), Photodetector Array Camera and Spectrometer (PACS), and Spectral and Photometric Imaging REceiver (SPIRE)). Here we present calculations of the expected spectra of Titan in the Herschel wavelength range. We investigate the possibility to retrieve vertical profiles of temperature and H2O, HCN, and CO mixing ratios in Titan's atmosphere with the instruments on-board for the expected signal-to-noise ratios. Our results in preparation for Herschel show our technique to be a promising tool for the analysis of Titan's atmospheric data. Last but not least, Herschel data will be retrieved, reduced and analyzed with an highly customizable and programmable software so-called Herschel Interactive Processing Environment (HIPE), which includes specific advanced modules for the three instruments. Spectral analysis tools already show a successful performance for our purposes. *also known as Herschel Solar System Observations' (HssO) project » topESC - "eScience: new tools for research in astronomy" K. Rieger Green Grid: High Speed with Low Power Consumption (Talk)Computing performance has grown and with it the power consumption. A way out of this dilemma are clusters with specialised hardware as GPUs and FPGAs. For astrophysical codes like NBODY6++ such clusters even outperform Blue Gene and other supercomputers. Sharing these clusters via modern grid based infrastructure using open technologies like Globus and GridWay allows many communities to use the new green hardware. » topCOS - "Recent advances in cosmology" F. Roepke The diversity of Type Ia supernova explosions in multidimensional models (Talk, registered after deadline)Type Ia supernovae (SNe Ia) are one of the prime tools in observational cosmology. A relation between their peak luminosities and the shape of their light curves allows to infer their intrinsic luminosities and to use them as distance indicators. This relation has been established empirically. However, a theoretical understanding is necessary in order to get a handle on the systematics in SN Ia cosmology. I will discuss different approaches to modeling SN Ia explosions. As I will show, a particular model - the delayed detonation scenario - has great potential to reproduce the bulk of SN Ia observations. Synthetic light curves from a two-dimensional implementation of this model follow the luminosity-light curve shape relation used in SN Ia cosmology. » topPLE - "Plenary session" S. Röser Open clusters and the Galactic disk (Highlight Talk)It is textbook knowledge that open clusters are conspicuous members of the thin disk of our Galaxy, but their role as contributors to the stellar population of the disk was regarded as minor. Only recently we found, from an unbiased sample of open clusters in the solar neighbourhood, that they contributed around 40 percent to the stellar content of the disk during the history of our Galaxy. I'll discuss, among others, the mass and luminosity functions of Galactic open clusters and their temporal evolution, as well as the integrated magnitudes and colours. The latter enable a comparison between the clusters in the Milky Way and in other galaxies. » topINS - "Innovations in spectroscopy" M.M. Roth, H-G. Löhmannsröben, A. Kelz, M. Kumke innoFSPEC Potsdam: fiber optical spectroscopy and sensing (Talk)innoFSPEC Potsdam is presently being established as interdisciplinary innovation center for fiber-optical spectroscopy and sensing, hosted by Astrophysikalisches Institut Potsdam and the Physical Chemistry group of Potsdam University, Germany. The center focuses on fundamental research in the two fields of fiber-coupled multi-channel spectroscopy and optical fiber-based sensing. Thanks to its interdisciplinary approach, the complementary methodologies of astrophysics on the one hand, and physical chemistry on the other hand, are expected to spawn synergies that otherwise would not normally become available in more standard research programmes. innoFSPEC targets future innovations for next generation astrophysical instrumentation, environmental analysis, manufacturing control and process monitoring, medical diagnostics, non-invasive imaging spectroscopy, biopsy, genomics/proteomics, highthroughput screening, and related applications. » topINS - "Innovations in spectroscopy" G. Rupprecht, S. Deiries, R. Hinterschuster, J.-L. Lizon, R. Reiss The MUSE detector system - a new dimension in collecting astronomical data (Talk)MUSE is one of the 2nd generation instruments for the ESO VLT. Its detector system is an essential and sophisticated component of the instrument, consisting of 24 4k×4k CCDs. Each CCD is mounted in its own independent detector head, serving one spectrograph. A common vacuum and cryogenic system ensures optimum conditions and safe operations for all detectors. Data acquisition will be done using ESO's newly developed New General detector Controller (NGC). We report about the performance of the devices and the challenges of the (mini) series production. » topCOS - "Recent advances in cosmology" D. Samtleben on behalf of the QUIET Collaboration The Q/U Imaging ExperimenT (QUIET) - measuring the CMB polarization with coherent detector arrays (Talk)The detection of the subtle signature of inflation in the CMB polarization pattern requires unprecedented sensitivity and control of foregrounds and systematics. QUIET addresses the challenges using large coherent detector arrays. The linear Stokes parameters Q and U are measured simultaneously in each pixel which provides a powerful handle on systematics. The selected frequencies (40/90 GHz) complement current bolometric approaches which is important for an efficient identification and removal of astrophysical foregrounds. We have started data taking with prototype arrays with 91 (19) elements at 90 (40) GHz in the Atacama Desert in Chile in the autumn of 2008. I will show the status and prospects for QUIET also for the expansion of the arrays to 1600 receivers which will reach sufficient sensitivity for the detection of the primordial gravity signature at a tensor to scalar ratio of r ~ eq 0.01. » topINS - "Innovations in spectroscopy" M.C. Sánchez Gil, E.J. Alfaro, E. Pérez Kinematical and physical properties of a 700 pc large bubble in NGC 6946 (Talk)The galaxy NGC 6946 contains a gas-star complex around 700 pc in diameter which appears populated by some tens of young stellar clusters, and a super star cluster as massive as one million solar masses. The gas as drawn by the Hα emission, delineates an almost circular shape which we show here to be in expansion. Previous studies have analyzed the stellar component of the complex, as well as the structure of the atomic and ionized gas, but these analyses were restricted to the blueshifted component. In this work we present a complete spectroscopic study of this object for two position angles crossing each other close to the young super massive central star cluster. We use a spectral resolution six times better than previous spectroscopic studies, and the atmospheric conditions were also better than those previously reported, allowing us to detect the approching and receding walls of one the largest bubbles in external galaxies ever studied in detail. The kinematical analysis shows a large expanding bubble, whose walls appear to be highly structured with superposed smaller shells, likely originated as the result of star forming events occurring at the edges of the larger scale shell, a la Huygens. We also estimated some diagnostic diagrams of the ionized gas yielding the conclusion that most of the currently observed ionization was originated by highly energetic photons and only a few portion of the gas shows line emission ratios compatible with shocks by stellar winds and/or supernova explosions. This peculiar complex is an excellent laboratory for the analysis of the interaction and feedback between the gas where the stars were formed and the young and massive generation of new born stars. » topCOS - "Recent advances in cosmology" A.G. Sanchez, M. Crocce, A. Cabre, C.M. Baugh, E. Gaztanaga Cosmological parameter constraints from SDSS luminous red galaxies: a new treatment of large-scale clustering (Talk)We apply a new model for the spherically averaged correlation function at large pair separations to the measurement of the clustering of luminous red galaxies (LRGs) made from the SDSS by Cabre & Gaztanaga (2008). Our model takes into account the form of the BAO peak and the large scale shape of the correlation function. We perform a Monte Carlo Markov chain analysis for different combinations of datasets and for different parameter sets. The correlation function measurements by themselves can constrain the dark energy equation of state parameter to w_DE = -1.02± 0.13, independently of CMB or supernovae data. When used in combination with a compilation of the latest CMB measurements, the LRG clustering and the latest supernovae results give constraints on cosmological parameters which are comparable and in remarkably good agreement, resolving the tension reported in some studies. The best fitting model in the context of a flat, Lambda-CDM cosmology is specified by Ω_m = 0.261± 0.011, Ω_b = 0.044± 0.001, n_s = 0.96± 0.01, H0 = 71.5± 1.1 km/s/Mpc and σ8 = 0.80± 0.02. If we allow the time-independent dark energy equation of state parameter to vary, we find results consistent with a cosmological constant at the 5% level using all data sets: w_DE = -0.97± 0.05. We do not find convincing evidence for an evolving equation of state. We provide a set of extended distance priors' that contain the most relevant information from the CMB power spectrum and the shape of the LRG correlation function which can be used to constrain dark energy models and spatial curvature. Our model should provide an accurate description of the clustering even in much larger, forthcoming surveys, such as those planned with NASA's JDEM or ESA's Euclid mission. » topINS - "Innovations in spectroscopy" C. Sandin Unfolding properties of mass loss at the rapidly changing tip of the asymptotic giant branch (Talk)In the final stages of stellar evolution low- to intermediate-mass stars lose their envelope in increasingly massive stellar winds. Matter, which has been processed inside such stars, is thereby returned to the interstellar medium. Such mass loss determines properties of subsequent planetary nebulae and white dwarves, and on longer time scales it also affects the galactic chemical evolution. In order to measure properties of winds near the tip of the asymptotic giant branch we observed weak halos of a set of planetary nebulae in the galactic disk. For this purpose we used the method of integral field spectroscopy together with a novel method of data analysis. The results show that mass loss rates increase strongly during the final mass loss stage -supporting expectations of previous observed tendencies and models. In this presentation I will demonstrate key results and concepts of our method, including a comparison with other methods. I will also present our approach towards a much extended study; more observations are needed to more precisely predict physical properties of this decisive stage of stellar evolution. » topISM - "Dynamical processes in the interstellar medium" C. Sandin, D. Schönberner, R. Jacob, M. Steffen, M.M. Roth On the chemical composition of the metal-poor planetary nebula PN G135.9+55.9 (Poster)The metal-poor and strange planetary nebula PN G135.9+55.9 has a particularly low oxygen abundance, that is a matter of an ongoing discussion. We report on our results of both new accurate observations by means of integral field spectroscopy with PMAS, and on the outcome of new radiation hydrodynamics models. Our goal with these studies was to calculate new abundance estimates. We find that expansion cooling, and deviations from thermal equilibrium, becomes increasingly important to the physical structure at metalicities that are as low as in this object. The resulting low electron temperatures cause substantial deviations in the abundances compared to an approach using standard hydrostatic photo-ionization models. » topINS - "Innovations in spectroscopy" C. Sandin, J. Gerssen, T. Becker, P. Böhm, L. Cairós, P. Weilbacher, A. Zwanzig, A. Monreal-Ibero, M.M. Roth Software demonstration: integral field spectroscopy data reduction made easy with P3d (Talk)Through integral field spectroscopy it is possible to attain large quantities of data rapidly. In order to speed up the data reduction process, and also make it less error-prone, semi-automatic tools - or pipelines - become highly valuable. The goal of our integral field unit data reduction tool P3d, that is being developed at AIP, is to create a (soon) freely available and general tool that will help you reduce your data. For a set of different instruments and object data we will demonstrate strengths, capabilities, and ease-of-use of P3d. » topGAL - "Galactic archaeology" C. Scannapieco The formation of spiral galaxies in a ΛCDM Universe (Talk)The formation of disk galaxies such as the Milky Way is still an open problem in cosmology. In particular, cosmological simulations have repeteadly failed in reproducing disk galaxies with properties comparable to observational counterparts, due to the so-called angular momentum catastrophe'. It is believed that feedback mechanisms, such as supernova (SN) feedback, play a key role in the formation of disk galaxies, regulating the star formation activity, producing important galactic outflows, and maybe contributing to prevent the angular momentum problem. In this talk, I will discuss the effects of SN feedback on the formation of disk galaxies, using high-resolution, SPH cosmological simulations which include star formation, chemical enrichment, a multiphase gas model and SN energy feedback. In particular, I will show how SN feedback affects the dynamical and chemical properties of the different components in galaxies (disk, bulge, stellar halo), through the redistribution of mass and metals produced by SN-driven galactic winds and fountains. The large amount of observational data being gathered in on-going surveys, in particular of chemical patterns in the Milky Way and satellite galaxies, will allow a much better comparison with predictions of simulations within a ΛCDM cosmology, and will allow to better understand how the different mass components in galaxies have been assembled. » topCOS - "Recent advances in cosmology" B.M. Schaefer Angular momentum correlations and intrinsic alignments of galaxies (Poster)Correlations between the angular momenta of neighbouring galaxies cause their ellipticities to be correlated physically, which is a source of contamination of weak lensing measurements. I present some results on the derivation of the angular momentum correlation function and the resulting ellipticity correlation function and discuss statistical properties of the ellipticity field such as intrinsic E and B-modes. » topACT - "Exoplanets, stellar activity, and the star-planet connection" S. Schäfer, F. Hessman, M. Hundertmark, S. Dreizler Testing General Relativity by observing gravitational microlensing with long-baseline interferometry (Poster)Due to the small separations of the observed images of microlensing events, it is difficult to determine all physical parameters from photometric lightcurves alone. With long-baseline interferometry providing a resolution in the milliarcsec range, one can resolve these images and break the mass degeneracy. Microlensing-survey programs like MOA and OGLE detect about 1000 events per year with ~ 10% binary events including planetary companions which are of special interest. Based on simulations we characterise the candidates which are most sensitive with respect to deviations from general relativity and are observeable with the VLTI. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" K. Scherer, H. Fichtner, S.E.S. Ferreira Anomalous cosmic rays as a source of low-energy Galactic cosmic rays (Talk)The present paradigm states that the sources of galactic cosmic rays are mainly supernova explosions or the like. We show here that solar like stars can contribute to a large amount to the low energetic part of the cosmic ray spectrum. The astrospheres around these stars transform the neutral atoms of the interstellar medium flowing towards the star into pickup ions, which are then transported in the astrosheath region where they are accelerated to higher energies (< GeV). The component of the high energetic particles penetrating back towards the Sun is the anomalous component of the cosmic rays. However, these energetic particles also leak into the interstellar medium, where they become part of the CR spectrum. Other wind driving stars may contribute to even higher energies which will be a topic of further research. Thus not only violent events contribute to the lower part of the cosmic ray spectrum, but there is also a continuous supply from main sequence star astrospheres. » topACT - "Exoplanets, stellar activity, and the star-planet connection" K. Scherer, S.E.S. Ferereira, H. Fichtner Different cosmic ray spectra at exoplanet orbits (Talk)The cosmic ray spectra at the position of an exoplanet depend not only on the stellar activity and the surrounding astrosphere, but also on the local interstellar environment. We discuss here different wind driving stars together with their possible local interstellar media, and the resulting cosmic ray flux at the orbit of an exoplanet. The cosmic ray spectrum has not only influence on lifeforms, but also on the reduction of biomarkers. The latter can be used as tracers for biological activity, and, therefore, their modification by cosmic rays is important to be known. » topGAL - "Galactic archaeology" E. Schilbach, S. Röser, R.-D. Scholz Trigonometric parallaxes, absolute magnitudes and IR-colours of ten ultracool subdwarfs (Talk)We measured absolute trigonometric parallaxes and proper motions with respect to many background galaxies for a sample of ten ultracool subdwarfs. Observations were taken in the H-band with the OMEGA2000 camera on the 3.5 m-telescope at Calar Alto, Spain during a time period of 3.5 years. For the first time, the reduction of the parallax measurements was carried out directly with respect to background galaxies. We obtained absolute parallaxes with mean errors ranging between 1 and 3 mas, the corresponding mean errors of the absolute magnitudes MKs range from 0.09 to 0.21, except for the most distant star with 0.56. With six completely new parallaxes we more than doubled the number of benchmark ultracool (> sdM 7) subdwarfs. Six stars in the MKs vs. J-Ks diagram fit perfectly to model subdwarf sequences from M 7 to L 4 with [M/H] between -1.0 and -1.5, whereas 4 are consistent with a moderately low metallicity ([M/H] = -0.5) from M 7 to T 6. All but one of our objects have large tangential velocities between 200 and 320 km/s typical of the Galactic halo population. » topMSC - Plenary session (posters only) F. Schiller, N. Przybilla, R.-P. Kudritzki, M.A. Urbaneja, F. Bresolin The flux-weighted gravity-luminosity relationship for BA-type supergiants in the Small Magellanic Cloud (Poster)We investigate fundamental properties of B and early-A type supergiants in the SMC - mainly on the basis of high-resolution, high-S/N FEROS spectra. Effective temperatures and surface gravities are derived from a detailed analysis of metal ionization equilibria and the Stark-broadened Balmer lines using an extensive non-LTE model grid of synthetic spectra. This allows for a precision calibration of the flux-weighted gravity-luminosity relationship (FGLR) - a purely spectroscopic distance indicator - in a metal-poor environment. The FGLR promises independent and tighter constraints on the extragalactic distance scale to be derived than possible with classical photometric indicators like Cepheids. » topISM - "Dynamical processes in the interstellar medium" D. Schleicher, M. Spaans, R. Klessen Probing the ISM of high-redshift quasars with ALMA (Talk)We explore the possibility to probe the ISM of high-redshift quasars with the mm/submm telescope ALMA. For such systems, two main mechanisms exist to excite molecular and finestructure line emission. On large scales, excitation via UV photons from the starburst is the dominant form of energy input, which will drive emission in dust and the finestructure lines of [C ii] and [O i]. In addition, the high resolution of ALMA makes it possible to probe the central region of ~ 200 pc, in which excitation via X-rays is the dominant mechanism that drives emission. For the central region, we present detailed calculations for the chemistry of molecular clouds irradiated by X-rays as well as quantitative predictions regarding the expected emission in high-J CO lines. The expected fluxes are strong enough for 3-sigma detection within less than a day at z = 10. As it is unclear whether quasars at that redshift are still at high metallicities, we show how predictions regarding the observed fluxes depend on metallicity and X-ray flux. We further present estimates regarding the expected number of sources at that redshift. » topISM - "Dynamical processes in the interstellar medium" S. Schmeja, M.S.N. Kumar, D.A. Gouliermis, R.S. Klessen Hierarchical star formation in a turbulent interstellar medium (Poster)The interstellar medium shows a hierarchical structure, sometimes described as self-similar or fractal, from the scales of the largest giant molecular clouds down to individual cores and embedded star clusters, which are sometimes hierarchical themselves and can be seen as the bottom parts of the hierarchy. Consequently, the structure of an embedded cluster, i.e. the spatial distribution of its members, may hold important clues about the formation mechanism and initial conditions. We will present the analysis of nascent star clusters ranging from nearby low-mass star-forming regions to large complexes in our Galaxy and the Magellanic Clouds. We analyse their structures using different statistical methods and discuss in particular the relation of the cluster structure to the turbulent molecular clouds they are formed in. » topPLE - "Plenary session" R. Schmidt X-ray spectroscopy and mass analysis of galaxy clusters (Highlight Talk)In this talk I use X-ray observations of galaxy clusters to study the properties of their dark matter halos. In particular, I will show how X-ray imaging-spectroscopy of the most X-ray luminous, dynamically relaxed clusters can be used to test predictions from cold dark matter simulations regarding the mass profile and the mass-concentration relation. When combined with galaxy velocity measurements, the kinematics of the galaxy cluster can be studied. » topMSC - Plenary session (posters only) W. Schmidt, A. Bell, T. Berkefeld, H-P. Doerr, B. Feger, R. Friedlein, K. Gerber, F. Heidecke, T. Kentischer, O. von der Lühe, M. Sigwarth, D. Soltau, O. Wiloth Active optics for the Sunrise balloon-borne telescope - in-flight performance of the Correlating Wavefront Sensor (Poster)The Sunrise balloon-borne solar telescope performed its first science flight from the Swedish Esrange Space Center to Somerset Island in North-East Canada from 8 to 15 June 2009. At a float altitude of about 36 km, the science instruments took sequences of broad-band images in the near UV, between 214 and 296 nm, as well as spectropolarimetric data in a photospheric line. A major challenge of balloon-born telescopes is the accurate pointing to the science target. Furthermore, temperature changes may lead to focus drifts. As a first compensation stage, Sunrise had a gondola pointing system that reduced wind-induced gondola swings during the flight to about 20 arcs (RMS). Secondly, a fast (90 Hz bandwidth ) image stabilization stage further reduced the image jitter down to 0.04 arcs RMS. For compensating temperature-induced focus errors, Sunrise used an autofocus system that reduced the focus error from 0.3λ (500 nm) RMS to 0.01λ RMS. Both the fast image stabilization and the autofocus unit are controlled by a Shack-Hartmann-sensor, and were developed at the Kiepenheuer-Institut. Sunrise is an international project, led by the Max-Planck-Institut für Sonnensystemforschung, with partners from Spain (IMAX consortium), the US (High Altitude Observatory, Boulder, Lockheed Martin Solar Laboratory, Palo Alto), and the Kiepenheuer-Institut für Sonnenphysik, Freiburg. » topMSC - Plenary session (posters only) L. Schmidtobreick, C. Tappert, B. Gaensicke The dwarf nova ASAS 153616-0839.1 (Poster)In February 2004, the outburst of a new eruptive star in Libra was reported as a VSNET alert. Lightcurves taken all over the world revealed that the object showed periodic variability with probably increasing period which could be interpreted as growing superhumps on a dwarf nova outburst of WZ Sge-type. At that time, we were able to confirm this classification spectroscopically and also took more data in the following years to analyse this object: Low resolution spectra covering a large optical range were taken on several epochs after the outburst to follow the decline; time resolved spectroscopy of the Hα emission line and simultaneous photometric lightcurves reveal the orbital variation of the binary and allow to determine some of the system parameters. On this poster, we will present and discuss the results of these observations. » topESC - "eScience: new tools for research in astronomy" T. Scholl, J. Müller, B. Gufler, A. Reiser, A. Kemper Scalable community-driven Data Grids (Talk)E-science communities and especially the astronomy community have put tremendous efforts to provide global access to their distributed scientific datasets. Beyond already existing huge data volumes, the collaborative researchers face major challenges in managing the anticipated data deluge of forthcoming projects with expected data rates of several terabytes a day and petabytes a year such as the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS), the Large Synoptic Survey Telescope (LSST), or the Low Frequency Array (LOFAR). Community-driven data grids target at domain-specific federations and provide a distributed, collaborative data management by employing dominant data characteristics (e.g., data skew) and query patterns to optimize the overall throughput. By combining well-established techniques for data partitioning and replication with Peer-to-Peer (P2P) technologies we can address several challenging problems: data load balancing, handling of query hot spots, and the adaption to short-term burst as well as long-term load redistributions. In our talk we provide an overview of HiSbase, our prototype for the proposed data management infrastructure developed within the AstroGrid-D project. » topHOT - "Magnetic fields in hot stars" G. Schönherr, J. Wilms, P. Kretschmar, I. Kreykenbohm, S. Suchy, R. Rothschild, A. Santangelo, R. Staubert Strong magnetic fields of neutron stars: what cyclotron lines can tell us (Talk, registered after deadline)Cyclotron resonant scattering features (CRSFs) are absorption-line-like structures seen in the spectra of several accreting X-ray pulsars in the hard X-ray range. The line positions give the only direct measure of a neutron star's magnetic field (except for gravitational redshift), which for X-ray pulsars, is of the order of 1012 Gauss. Studying the line profiles in more detail allows to gain insight in the physical conditions of the accretion columns. By comparison of the observationally resolved line profiles to theoretical predictions, one finds more and more hints for a complex magnetic field structure. » topCOS - "Recent advances in cosmology" T. Schrabback Cosmological weak lensing with COSMOS (Talk)Future weak gravitational lensing surveys promise to deliver tight constraints on the nature of dark energy. So far most constraints have been comparatively weak due to limited survey size and, in particular, the lack of photometric redshifts. These are required to probe the impact of dark energy on the growth of structure and the redshift-dependent geometric lensing efficiency. A perfect test case is given by the COSMOS Survey, which combines accurate space-based weak lensing measurements with excellent ground-based photometric redshifts. I will present our independent cosmological weak lensing analysis of the COSMOS data, summarize our new treatment of various systematic effects, and focus on the measurement of the redshift dependence of the shear signal. I will briefly discuss implications for future surveys. » topPLE - "Plenary session" S. Schuh Pulsations and planets: the asteroseismology-extrasolar-planet connection (Biermann Talk)The disciplines of asteroseismology and extrasolar planet science overlap methodically in the branch of high-precision photometric time series observations. Light curves are, amongst others, useful to measure intrinsic stellar variability due to oscillations, as well as to discover and characterize those extrasolar planets that transit in front of their host stars, periodically causing shallow dips in the observed brightness. Both fields ultimately derive fundamental parameters of stellar and planetary objects, allowing to study for example the physics of various classes of pulsating stars, or the variety of planetary systems, in the overall context of stellar and planetary system formation and evolution. Both methods typically also require extensive spectroscopic follow-up to fully explore the dynamic characteristics of the processes under investigation. In particularly interesting cases, a combination of observed pulsations and signatures of a planet allows to characterize a system's components to a very high degree of completeness by combining complementary information. The planning of the relevant space missions has consequently converged with respect to science cases, where at the outset there was primarily a coincidence in instrumentation and techniques. Whether space- or ground-based, a specific type of stellar pulsations can themselves be used in an innovative way to search for extrasolar planets. Results from this additional method at the interface of stellar pulsation studies and exoplanet hunts in a beyond-mainstream area will be presented. » topACT - "Exoplanets, stellar activity, and the star-planet connection" S. Schuh, R. Silvotti, and the EXOTIME collaboration Planetary systems around evolved stars (Poster)The majority of extrasolar planets are found around hydrogen core burning main sequence stars since this is the longest-lived phase in the live of a star, and the radial velocity method is most readily applied to these host stars. Beyond the main sequence phase, planets have been found around subgiant stars at the beginning of the red giant branch, and the first planet-like objects ever discovered were in fact found around pulsars. In between the highly evolved pulsars, and stars evolved just beyond the main sequence, planetary systems found around extreme horizontal branch stars allow to separate the effects of the red giant branch from those of the asymptotic giant branch evolution. » topISM - "Dynamical processes in the interstellar medium" M.M. Schulreich, D. Breitschwerdt Astrophysical bow shock waves - comparison of analytical and numerical models (Talk)Bow shock waves as a result of the supersonic motion of objects through a compressible medium, like e.g. galaxies through the surrounding intergalactic medium are a common phenomenon in galaxy groups and clusters. We will present an analytical solution method for the astrophysical hypersonic blunt body problem, and compare it to numerical gas-dynamical simulations as well as Chandra and XMM-Newton observations of Stephan's Quintet (Trinchieri et al. 2003, 2005). Our results support the picture that the observed surprisingly low post-shock temperatures visible in the X-ray emission of Stephan's Quintet originate from a prominent oblique shock produced in the hypersonic collision of NGC 7318b with previously stripped H i gas. Main advantages of the analytical model are its validity in the whole flow region, and that it takes in particular into account velocity gradients along the streamlines. The method's relevance for other astrophysical research fields involving bow shock waves, which are common in the interstellar medium, will be discussed as well. » topMSC - Plenary session (posters only) S. Schwesig, F. Hessman, S. Wolff, S. Dreizler, M. Hundertmark Implementing a new pointing model for MONET/North (Poster)The Altitude/Azimuth mounted MONET/North telescope is remotely operated using a web-based control interface. Although the first pointing model is sufficiently accurate to keep the observed object roughly at the center of the field of view an improved model is required for longer exposure times.We have measured an improved pointing model using a grid of more than 100 bright stars over an altitude of 10 to 80 degrees and the full azimuthal range. For each point of the grid we have measured the offset between the instrumental position and the real position of our objects. The model parameters were determined using a standard multidimensional linear model. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" E. Sedlmayr Physics and chemistry of cosmic dust: from the origin to planetary matter (Talk)Cosmic dust plays an important role in the cosmic evolution of matter essentially in three ways: Its presence may influence dramatically as well the dynamical as the energetical behaviour of matter, and also triggers strongly its chemical evolution, in this way being of decisive importance for the cosmic circuit of matter. Especially the dynamical phases of this circuit, starting with transforming interstellar matter into stars, with the crucial role of dust cooling, and on the other end by transforming stellar matter into ISM, driven by massive dusty stellar winds at the end of stellar evolution, in particular for low and medium mass stars during their red giant and AGB-phase, respectively. Opposite to the direction of this evolution of cosmic matter is that one of the dust complex: The primary grains condense and grow in the cooling winds of late type objects and are expelled into the ISM, where these first grain components are strongly processed - mostly in fact are completely annihilated - by forming new kinds of grains in the ISM, which then take part in the formation of new stars and eventually planetary systems. During this chain of dust evolution many signatures of the primary formation are preserved and are still found by means of laboratory studies of presolar material, as in certain meteorites. The aim of the talk is to discuss the actual picture of dust evolution by following this causal sequence of dust formation, destruction, and reformation. » topACT - "Exoplanets, stellar activity, and the star-planet connection" U. Seemann, A. Seifahrt, A. Reiners The Hα limit in the Hyades (Poster)We present a study of K to M type stars in the Hyades. We use a large sample in this intermediate-age cluster ( ~ 650 Myr) to probe a threshold region where magnetic wind braking becomes ineffective and stars have not yet spun down to the rotation rate found on the main sequence. Our results on rotational velocities (v sin i) and activity indicators (Hα, Ca ii H+K) shed light on the question whether the threshold to rapid rotation in the field stars and the Hyades stars is different. » topINS - "Innovations in spectroscopy" U. Seemann, H.U. Käufl, A. Reiners Brownies in the near Infrared (Poster)Brown Dwarfs occupy the substellar regime between stars and planets. Their detailed study is a challenge under both technological and theoretical aspects, and high-resolution spectroscopy of these ultra-faint objects has become accessible only recently. The systematic study of their properties in the near infrared is limited by the availability of suitable instruments and by the lack of molecular data. Their atmospheres comprise complex molecular features and the creation of dust, both are not well understood to date. We present our efforts to investigate the magnetic fields of Brown Dwarfs with ESO's high-resolution NIR spectrograph CRIRES. As the spectra can only poorly be modeled to date, we search for tracers that allow for a consistent determination of magnetic Flux in the IR. We also outline the potential of spectro-polarimetric measurements in the IR which would allow to infer the magnetic properties from Zeeman splitting of suitable spectral lines. » topINS - "Innovations in spectroscopy" W. Seifert, N. Ageorges, M. Juette, V. Knierim, M. Lehmitz, P. Buschkamp, C. Feiz, H. Gemperlein, A. Germeroth, R. Hofmann, W. Laun, R. Lederer, R. Lenzen, U. Mall, H. Mandel, P. Mueller, V. Naranjo, A. Pasquali, K. Polsterer, L. Schaeffner, A. Quirrenbach, R. Genzel, R.-J. Dettmar, H.-W. Rix Commissioning and first light of LUCIFER at the Large Binocular Telescope (Poster)LUCIFER is a NIR spectrograph and imager (wavelength range 0.9 to 2.5 micron) for the Large Binocular Telescope (LBT) on Mt. Graham, Arizona, working at cryogenic temperatures of less than 70K. Two instruments are built by a consortium of five German institutes and will be mounted at the bent Gregorian foci of the two individual telescope mirrors. Three exchangable cameras are available for imaging and spectroscopy: two of them are optimized for seeing limited conditions, a third camera for the diffraction limited case will be used with the LBT adaptive secondary mirror working. Up to 33 exchangeable masks are available for longslit or multi-object spectroscopy (MOS) over the full field of view. At present, the commissioning of the first LUCIFER instrument at the LBT in seeing-limited mode is almost complete. In this contribution, the main characteristics of the instrument will be outlined and the first results obtained during commissioning be shown and be discussed. » topPLE - "Plenary session" K. Sembach The multi-phase interstellar medium in and around galaxies (Review Talk)In this talk, I will present an overview of spectroscopic observations of the multi-phase interstellar medium in and around galaxies in the low-redshift universe, with particular emphasis on the Milky Way and nearby galaxies. Since much of this work depends upon access to spectral line diagnostics at ultraviolet wavelengths, I will also describe the spectroscopic capabilities of the refurbished Hubble Space Telescope and the role its instruments may play in future studies of galactic halos. » topCOS - "Recent advances in cosmology" O. Sergijenko Two-field model of dark energy with canonical and non-canonical kinetic terms (Poster)The phantom divide crossing is not allowed for single fields with the simplest Lagrangians, however it is possible for the 2-field models of dark energy including both quintessence and phantom. We focus on the model given by Lagrangian with a canonical kinetic term and a Dirac-Born-Infeld one: L = -(φ;iφ;i-U(φ,ξ)√1-ξ;iξ;i)/2. For such case the potentials U(φ,ξ) are reconstructed using the modern observational data. The existing ambiguities and necessary additional assumptions are dicussed. » topMSC - Plenary session (posters only) O. Smirnova, L. Zacs High-resolution spectroscopy of cool R CrB star candidates V1983 Cyg and V2074 Cyg (Poster)R Coronae Borealis (R CrB) stars are rare type of hydrogen-deficient, carbon-rich evolved stars which undergo strong, irregular brightness variations in the optical region. Only about 50 R CrBs have been identified in the Milky Way. The evolutionary models imply relative populations of R CrBs with effective temperature, T_eff = 5000, 6000, and 7000 K of 30:5:1, however, most of the known Galactic R CrBs fall into the warmest subgroup. The preliminary results of high-resolution spectroscopy in the optical region are presented for two cool R CrB candidate stars. V1983 Cyg and V2074 Cyg are suspected to be cool R CrB stars by photometric study; sudden light declines typical for R CrB variables have been detected. In the high-resolution spectra prevail absorption features of C2 and CN molecules indicating low temperature and enhanced carbon abundance. Blueshifted circumstellar components in the sodium resonance lines confirmed high-speed ejection of matter with a velocity of about 60 km/s. Effective temperature, luminosity, hydrogen abundance and metallicity are estimated for the first time. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" T. Spohn Planetary evolution and habitability (Talk)Planetary habitability is usually thought to require water on (or near) the surface, a magnetic field to protect life against cosmic radiation, and transport mechanisms for nutrients. A magnetic field also serves to protect an existing atmosphere against erosion by the solar wind and thus helps to stabilize the presence of water and habitability. Magnetic fields are generated in the cores of the terrestrial planets and thus habitability is linked to the evolution of the interior. Moreover, the interior is a potential source and sink for water and may interact with the surface and atmosphere reservoirs through volcanic activity and recycling. On the Earth, water is stabilized by complex interactions between the atmosphere, the biosphere, the oceans, the crust, and the deep interior. The most efficient known mechanism for recycling is plate tectonics. Plate tectonics is known to operate, at present, only on the Earth, although Mars may have had a phase of plate tectonics as may have Venus. Single-plate tectonics associated with stagnant lid convection can also transfer water from the interior but a simple recycling mechanism is lacking for this tectonic style. Stagnant lid convection will evolve to thicken the lid and increasingly frustrate volcanic activity and degassing. (This can keep the interior from running completely dry.) Plate tectonics also supports the generation of magnetic fields by effectively cooling the deep interior. (In addition, plate tectonics rejuvenates nutrients on the surface and generates granitic cratons.) For Mars and Venus it is likely that a present-day magnetic field would require plate tectonics to operate. An early field is possible even with stagnant lid convection but the dynamo will only operate less than about a billion years. This dynamo would have been driven by thermal buoyancy and require that the core was sufficiently superheated with respect to the mantle after core formation. The dynamo would have ceased to operate as the core cooled depending on the vigor of mantle convection. A question is then whether or not plate tectonics existed on Mars and Venus and if yes why plate tectonics ceased to operate. Or, more generally, why do planets have plate tectonics and others do not? Convection model calculations suggest relations to the yield strength of the mantle and the effect of water on the latter. Other models suggest that the existence of an asthenosphere (a low viscosity zone underneath the lithosphere) may be decisive. The presence of water will lower the solidus of mantle rock and help to form an asthenosphere. Thus, there appear to be links between plate tectonics and (near) surface water, plate tectonics and magnetic fields, magnetic fields and habitability, and habitability and water. Is plate tectonics even a potential biosignature? » topCOS - "Recent advances in cosmology" Y.H. Sreedhar, A.P. Odell, K.D. Rakos, G. Hensler Narrowband photometry and evolution of galaxies in Abell 1656 (Coma Cluster) (Poster)Hierarchical and Monolithic collapse models forms the basis for our understanding of the galaxy formation in the universe. Ages of the first stars, marks an important parameter in studying the early type galaxies, in field and clusters. The Strömgren uvby filters is a perfect and powerful tool for the determinations of stellar parameters (e.g. age, metallicity, surface temperature), in elliptical galaxies, and also has been used to investigate the spectrophotometric evolution of elliptical galaxies. The uniqueness of this technique is to observe the change in colors, of stars with short exposure imaging and also poses the advantage of breaking the age-metallicity degeneracy problem (Worthey, 1999). Rakos et al. (2007) has successfully shown, using the color- magnitude studies of existence of bi-modal feature of galaxy populations at low z, which have also been confirmed by Strateva et al. (2001), Blanton et al. (2003). Using the same feature of narrowband multi color and color-magnitude diagrams we exhibit our recent work with Abell 1656 (Coma Berenices) a dense, elliptical rich cluster with wide range of metallicity and displaying bi-modality with our age sensitive indices, hinting to the fact that majority of galaxies have red, passive colors usually associated with ellipticals and S0 morphologies. » topSOL - "The Solar System - our astrosphere: from space physics to astrophysics" M. Steffen, S. Wedemeyer-Böhm, H.-G. Ludwig, E. Caffau, B. Freytag Confronting 3D models of the solar photosphere with observations (Talk)We review the successes and failures of state-of-the-art 3D radiation-hydrodynamical simulations of solar surface convection in reproducing and explaining a variety of modern observations. For this purpose, we compare synthetic data computed from 3D CO5BOLD models with corresponding observations, including seeing-free high-resolution continuum images of the quiet solar granulation taken with the Solar Optical Telescope (SOT) onboard Hinode, and high-quality spectra taken with ground-based facilities at different positions on the solar disk. The key quantities to be checked for consistency are (i) the center-to-limb variation of the emergent intensity, (ii) the value of the continuum intensity contrast (as a function of limb angle), and (iii) the shape and Doppler shift of different spectral lines across the solar disk. In general, we find an excellent agreement between numerical models and observations, thus qualifying 3D models to be applied to other solar-type stars, and to be used for accurate abundance determinations, even though some discrepancies still remain to be understood. » topGAL - "Galactic archaeology" M. Steinmetz and the RAVE collaboration Unraveling the structure and kinematics of the Milky Way with RAVE (Talk)I will give an overview of the current state of the RAdial Velocity Experiment (RAVE), a survey with the goal of measuring spectra in the Ca triplet region for up to 1 million stars. I will discuss the performance of the survey, in particular with respect to the accuracy of the derived radial velocities and element abundances. Furthermore, I will present first science results. These include deriving constraints on the escape velocity of the Milky Way, the vertical structure of the thin and thick galactic disk and the search for in-falling stellar streams on the local Milky Way disk. » topGAL - "Galactic archaeology" J. Storm, T.G. Barnes, P. Fouque, W. Gieren, T. Granzer, N. Nardetto, K. Strassmeier, M. Weber Towards a new Galactic Cepheid Period-Luminosity relation (Poster)Using the STELLA spectrograph we are expanding the sample of galactic Cepheids with accurate radial velocity curves. This allows direct distances to be determined for a total of almost 80 stars using the IR surface-brightness method thus redefining the Galactic Cepheid Period-Luminosity (PL-) relation. This relation can be applied directly to samples of Cepheid in other large galaxies without having to worry about possible metallicity effects which might be apply to LMC based PL-relations. We discuss the theoretical and empirical constraints on the p-factor, the conversion factor between radial velocity and pulsation velocity and the effects on the resulting PL-relations. » topACT - "Exoplanets, stellar activity, and the star-planet connection" B. Stracke , J.L. Grenfell, P. von Paris, B. Patzer, H. Rauer The inner boundary of the habitable zone for Earth-like planets (Poster)Liquid water is a commonly accepted, fundamental requirement for the development of life. Based on this condition the Habitable Zone (HZ) is usually defined as the region of orbits around a star where liquid water exists on the surface of a terrestrial planet. The inner boundary of the HZ can be defined in different ways. The water loss limit' occurs where an Earth-like planet loses its entire water content within the planet's lifetime. The `runaway greenhouse' limit marks the point where the greenhouse effect becomes unstable via water evaporation. We present here a thorough study of the inner boundaries of the HZ around solar-type stars. To investigate these inner boundaries a one-dimensional radiative-convective model of the atmosphere is applied to different planetary system scenarios. Our modelling approach involves the step-by-step increase of the incoming stellar flux and the subsequent calculation of resulting changes in the atmospheric water vapour content and the radiative properties. To achieve this, the infrared radiative transfer scheme was improved to be suitable for such high temperature and pressure conditions. Modelling results are presented for the influence of various planetary and atmospheric conditions on the inner boundaries of the HZs around solar-type stars. » topELT - "The E-ELT - status, timeline, and instrumentation" K.G. Strassmeier, D. Baade, N.E. Piskunov, C. Keller, G.A. Hussain, S. Hubrig The science cases for spectropolarimetry at the E-ELT (Talk)A broad suite of scientific topics requiring (spectro)polarimetry with the E-ELT is presented. Among the science targets are solar-system objects, stars throughout the H-R diagram, degenerate objects, supernovae and their remnants, proto-planetary disks, the interstellar and intergalactic medium, AGNs, gamma-ray bursters and repeaters and even the early universe. Polarization of light always reveals some type of asymmetry at the stage of its emission or absorption or during its transfer to the observer, as is usually the case in astrophysical objects. The fundamental physical processes that are involved appear in targets from the Moon to the most distant quasars. Because spectropolarimetry is always light starving (even for the Sun), with a properly designed polarimeter on the E-ELT, polarimetry can be achieved more effectively from the ground than from space, as long as the desired wavelength is in a region of atmospheric transmission. This makes it all the more important to include polarimetric facilities on future ground-based extremely large telescopes. » topINS - "Innovations in spectroscopy" K.G. Strassmeier, I. Ilyin, M. Weber, T. Carroll, M. Steffen Ultra-high resolution spectroscopy with PEPSI: the Potsdam Echelle Polarimetric and Spectroscopic Instrument for the Large Binocular Telescope (Talk)The UHR mode of PEPSI will deliver an unprecedented spectral resolution of approximately R = 300,000 at high efficiency in the entire optical/red wavelength range (390-930 nm) without the need for adaptive optics. Besides its polarimetric Stokes IQUV mode, the capability to cover the entire optical/red range in three exposures at resolutions of 40,000, 120,000 or 300,000 will surpass existing facilities in terms of light-gathering-power times spectral-coverage product. A solar feed will make use of the spectrograph also during day time for PSF monitoring and solar physics. As such, we hope that PEPSI will be the most powerful spectrometer of its kind for the years to come. In this presentation, we summarize the PEPSI core projects and data products for its science definition phase in 2011. » topACT - "Exoplanets, stellar activity, and the star-planet connection" K.G. Strassmeier, J. B. Rice, M. Kopf, T. Carroll Doppler imaging the PMS star V410 Tau: a comparison of different inversion codes (Poster)We present Stokes I and V line-profile inversions of the active pre-main sequence star V410 Tau. The inversion process is based on our two codes TempMap and iMAP. While the former uses either a maximum entropy or Thikhonov regularization based on selected atomic spectral lines, the latter is based on a regularization-free inversion from a principal component analysis of nearly thousand lines. Very good agreement between the images is found. The star was also caught in the action of a large flare that excited and redshifted magnetically sensitive emission lines by 200 km/s and even affecting optically thin lines in their red absorption wings. We also present an inversion map from the molecular bandhead of TiO at 705.5 nm and discuss its relation to atomic lines. » topCOS - "Recent advances in cosmology" M. Sullivan, on behalf of the SNLS Cosmology with Type Ia Supernovae (Talk)I will review the use of Type Ia Supernovae (SNe Ia) in constraining the cosmological parameters. I will show the latest results from the CFHT Supernova Legacy Survey (SNLS), using ~ 250 SNe Ia over 0.1
last update August 28, 2009, R. Arlt