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Humboldt Research Fellowship for Jenny Sorce

Jenny Sorce (Credit: AIP).

Humboldt Research Fellowship for Jenny Sorce

22 October 2014. The Leibniz Institute for Astrophysics Potsdam (AIP) welcomes Jenny Sorce, who received a Humboldt Research Fellowship for Postdoctoral Researchers.

For the next two years she will collaborate with the AIP cosmologists at the intersection of the international projects CosmicFlows and CLUES.

Jenny Sorce obtained her bachelor of science at the Ecole Normale Superieure de Lyon and got her PhD in Astrophysics, Cosmology at the Universities of Lyon and Potsdam under the supervision of Prof.  Helene Courtois and Professor Matthias Steinmetz. During her PhD, she also worked in close collaboration with Dr. Stefan Gottlöber and the Wempe awardees of 2010 and 2014 Professor Brent Tully and Professor Yehuda Hoffman. She spent her research time between Lyon, Potsdam and Hawaii.

Jenny measured surface photometry of galaxies to obtain their distances using the Tully-Fisher relation. These accurate distance estimates allow for mapping the local deviations from the Hubble expansion, i.e. the radial peculiar velocities of galaxies. Based on these observational data it is possible to reconstruct the state of the local Universe some 13 billion years ago and to use this information as constrained initial condition for numerical simulations. Such constrained simulations are an excellent tool to study the evolution of the Milky Way.

Contakt: Dr. Jenny Sorce, jsorce@aip.de, +49 331 7499-647

Media contact: Kerstin Mork, presse@aip.de, +49 331 7499-469

The key topics of the Leibniz Institute for Astrophysics Potsdam (AIP) are cosmic magnetic fields and extragalactic astrophysics. A considerable part of the institute's efforts aim at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. Since 1992 the AIP is a member of the Leibniz Association.

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 An unprecedented view of two hundred galaxies

A panoramic view of the properties of galaxies.

An unprecedented view of two hundred galaxies

1 October 2014. The second data release of the international project CALIFA - a survey of galaxies carried out at Calar Alto observatory – will take place today. Galaxies are the result of an evo...

“The data corresponding to the hundred galaxies included in the first data release of November 2012 have already been downloaded more than seven thousand times and they have produced a wide variety of results, both from inside and outside the CALIFA collaboration" underlines Sebastián Sánchez, principal investigator of the project. "With more than thirty peer review publications, more than hundred contributions to scientific meetings and five PhD theses submitted, this project is the most productive among those ever carried out at Calar Alto. This data release is a new milestone of the project, which already can be considered an international reference in the field of extragalactic surveys”.

The CALIFA Project allows not only to inspect the galaxies in detail, but it also provides with data on the evolution of each particular galaxy with time.

Thanks to the CALIFA data, the astronomers have been able to deduce the history of the mass, luminosity and chemical evolution of the CALIFA sample of galaxies, and thus they have found that more massive galaxies grow faster than less massive ones, and that they form their central regions before the external ones (inside-out mass assembly). CALIFA has also shed light on how chemical elements needed for file are produced within the galaxies or on the physical processes involved on galactic collisions, and it has even observed the last generation of stars still in their birth cocoon.

The above picture shows:  1) broad band images (center up), 2) stellar mass surface densities (upper right), 3) average stellar ages (lower right), 4) diagnostic emission lines (lower center), 5) Halpha emission (lower left) and 6) kinematics (upper left). (Credits: R. Garcia-Benito, F. Rosales-Ortega, E. Pérez, C. J. Walcher, S. F. Sanchez and the CALIFA team)

Science contact: Dr. Jakob Walcher, +49 331-7499 243, jwalcher@aip.de
Media contact: Kerstin Mork , +49 331-7499 469, presse@aip.de

The key topics of the Leibniz Institute for Astrophysics Potsdam (AIP) are cosmic magnetic fields and extragalactic astrophysics. A considerable part of the institute's efforts aim at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. Since 1992 the AIP is a member of the Leibniz Association.

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Matthias Steinmetz elected President of the German Astronomical Society

Professor Matthias Steinmetz.

Matthias Steinmetz elected President of the German Astronomical Society

24 September 2014. Prof. Dr. Matthias Steinmetz, scientific chairman of the Leibniz Institute for Astrophysics Potsdam (AIP), is the new President of the German Astronomical Society (Astronomische ...

Matthias Steinmetz studied mathematics and physics in Saarbrücken and at the Technical University Munich. He received his doctorate in physics in Munich in 1993 and initially worked at the Max Planck Institute for Astrophysics in Garching. In 1996, aged 30, Matthias Steinmetz accepted a faculty position at the University of Arizona in Tucson. In 2002, he was appointed director of the AIP and professor at the University of Potsdam. Steinmetz was also visiting researcher at the University of California at Santa Barbara and Berkeley. His area of expertise is computational astrophysics and cosmology. Matthias Steinmetz has successfully engaged in particle hydrodynamics simulations of cosmological environments as well as in simulations of dark matter in the Galactic halo. Large surveys of the Milky Way, which are associated with his name, enabled new findings regarding the field of the galactic dynamics and the properties of kinematical groups of stars. He is also German speaker of the International Astronomical Union and advisor and member of several committees within the scientific community.

 

Prof. Dr. Joachim Wambsganß, Director of the Zentrum für Astronomie der Universität Heidelberg, has been elected vice president.

 

The German Astronomical Society, founded in 1863, is a modern astronomical society with more than 800 members dedicated to the advancement of astronomy and astrophysics and the networking between astronomers. It represents German astronomers, organises scientific meetings, publishes journals, offers grants, recognises outstanding work through awards and places a high priority on the support of talented young scientists, public outreach and astronomy education in schools.

(Press release of the German Astronomical Society)

 

Media Contact AG: Dr. Klaus Jäger, +49 6221 – 528 379, jaeger@mpia.de

Media Contact AIP: Kerstin Mork, +49 331 7499 469, presse@aip.de

The key topics of the Leibniz Institute for Astrophysics Potsdam (AIP) are cosmic magnetic fields and extragalactic astrophysics. A considerable part of the institute's efforts aim at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. Since 1992 the AIP is a member of the Leibniz Association.

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Astronomers unveil secrets of giant elliptical galaxies

Velocity map of M87.

Astronomers unveil secrets of giant elliptical galaxies

12 September 2014 Davor Krajnović, astronomer at the Leibniz Institute for Astrophysics Potsdam (AIP), and his colleagues Eric Emsellem (ESO) and Marc Sarzi (University of Hertfordshire), have dis...

The three astronomers observed the giant galaxy M87 (NGC4486), which is the central galaxy in the Virgo cluster, and discovered that it displays some bulk rotation, albeit of a very low amplitude. The precision of MUSE allowed the team to reveal that the stars of M87 can move around its centre with average velocities of just 10-20 km/s. Equivalent to 36-72,000 km/h, this speed may seem very high, but for galaxies this is extremely slow.

Elliptical galaxies have long been considered as essentially being made up of old stars that move randomly within them, like a swarm of bees. This has been challenged in many instances in the past ten-twenty years, but giant elliptical galaxies are still considered as a nearly round and non-rotating group of old stars.

By showing that a "simple" galaxy like M87 can be quite complicated in the eyes of the new MUSE spectrograph, this result demonstrates the potential of this new instrument for further advancing our understanding of galaxies, and their formation. Davor Krajnović states: “MUSE has the capability to enhance our understanding of galaxies, how they form and develop. By using the MUSE velocity data to constrain simulation models, we might reach a whole new level of precision.” Their work is published in the Monthly Notices of the Royal Astronomical Society and a pre-publication version of the paper is available on arXiv: http://arxiv.org/abs/1408.6844.

The Multi Unit Spectroscopic Explorer (MUSE) is a 3D-spectrograph for the Very Large Telescope (VLT) of the European Southern Observatory at Paranal (Chile). MUSE features a complex optical system with the capacity to split and slice a field that measures one square arcminute on the sky into 90,000 spatial elements. For each point a spectrum is created, covering the optical and near infrared wavelength region of 465-930nm. AIP provides the Data Reduction Software and operates one of the data centres accessible to scientists from all over the world.

 

(Click to enlarge)

Left: Image of M87: Some small companions galaxies of this giant and round elliptical galaxy are visible to the right of the image. The red square delineates the field-of-view of the MUSE instrument, where the velocity of the central stars of M87 have been measured.

Right: A map for the average velocity of the stars in the central region of M87, divided in polygonal regions where the MUSE data have been combined to reach a sufficient quality for these measurements. After accounting that M87 as a whole is moving away from us, red or yellow bins show stars that on average are receding whereas blue or light azure bins show stars that on average are approaching. The MUSE map reveal a complex motion of the stars in M87, where stars move in one way in the central region and in another in its outskirts.

 

Further information:

 

Science contact: Dr. Davor Krajnović, +49 331-7499 237, dkrajnovic@aip.de

Media contact: Kerstin Mork , +49 331-7499 469, presse@aip.de

 

The key topics of the Leibniz Institute for Astrophysics Potsdam (AIP) are cosmic magnetic fields and extragalactic astrophysics. A considerable part of the institute's efforts aim at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. Since 1992 the AIP is a member of the Leibniz Association.

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Facets of Solar Magnetic Fields

High-resolution G-band images.

Facets of Solar Magnetic Fields

3 September 2014. Magnetic fields on the solar surface come in many shapes and sizes. The smallest magnetic flux elements become visible in the Fraunhofer G-band, a narrow spectral region with many...

Magnetic flux ropes generated in the solar interior can become buoyant and start to rise. When such a flux loop reaches the surface, a bipolar emerging flux region (EFR) appears in the photosphere. The EFR represents the intersection of the inverse U-shaped flux bundle with the solar surface. However, only a small fraction of sunspots grows beyond this stage and matures to develop a penumbra with a radial filamentary structure that surrounds the dark core of the sunspot. This umbra can contain bright umbral dots and dark umbral cores, which are separated by bright, elongated light-bridges. One of the prime objective of the newly commissioned 1.5-meter GREGOR solar telescope is to investigate the interaction of magnetic fields and plasma motions at the highest spatial and temporal resolution.

The “early science phase” of the GREGOR solar telescope started in May 2014 using the Grating Infrared Spectrograph (GRIS). The Leibniz Institute for Astrophysics Potsdam (AIP) is in charge of the GREGOR Fabry-Pérot Interferometer (GFPI), an imaging spectropolarimeter for high-resolution photospheric and chromospheric observations. AIP’s research group for Optical Solar Physics organized a 50-day observing campaign in July/August 2014, where all members and partners of the GREGOR consortium proposed scientific tasks, which were then jointly carried out by a team of experienced observers at Observatorio del Teide, Izaña, Tenerife. Data processing is in full swing and the initial outcome indicates excellent performance of telescope and instruments. First scientific results will be presented at the fall meeting of the Astronomische Gesellschaft in Bamberg on 2014 September 25/26 in a special forum dedicated to “High-Resolution Solar Physics”.

The 1.5-meter GREGOR solar telescope was built by a German consortium under the leadership of the Kiepenheuer Institute for Solar Physics in Freiburg with the Leibniz Institute for Astrophysics Potsdam, the Institute for Astrophysics Göttingen, and the Max Planck Institute for Solar System Research in Göttingen as partners, and with contributions by the Instituto de Astrofísica de Canarias and the Astronomical Institute of the Academy of Sciences of the Czech Republic.

 

Picture
click to enlarge

High-resolution G-band images. bright points, pores, an emerging flux region, and a sunspot with umbral dots and light-bridges. The data were captured with the Blue Imaging Channel (BIC) of the GFPI in July 2014.

Movie: click

 

Media Contact: Kerstin Mork , +49 331 7499 469, presse@aip.de

The key topics of the Leibniz Institute for Astrophysics Potsdam (AIP) are cosmic magnetic fields and extragalactic astrophysics. A considerable part of the institute's efforts aim at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. Since 1992 the AIP is a member of the Leibniz Association.

Read more ...