Cool Stars 17 - Splinter Session "Differential rotation in theory and observation"
Tuesday afternoon, June 26, 2012
Scientific outline:
Understanding stellar activity means understanding the stellar dynamo. An essential ingredient to any astrophysical dynamo is the differential rotation. Measuring the differential rotation on a variety of low-mass stars is as crucial as the detection of stellar activity cycles. With all the experiences in Doppler imaging and the availability of high-precision photometry thanks to CoRoT and Kepler, it is time to compare analysis methods for the reconstruction of spots and the surface differential rotation. We will also be able to compare the observations with the theoretical predictions which have reached a very good agreement with the solar internal rotation. The latter was obtained by helioseismology, and it will also be highly interesting whether asteroseismology is going to be capable of inferring the internal rotation of stars.
There is also the interplay between magnetic fields and differential rotation which can not only support dynamo action but also lead to instabilities. Hydrodynamic shear instability as well as magnetic kink-type instabilities and the magneto-rotational instability have been studied in the solar tachocline. It will be very interesting to see how differently these instabilities behave for other rotation profiles.
We believe that it is now time to compare methods and models. The discussion will be beneficial for obtaining significant results on the differential rotation of stars. Without the knowledge of rotation profiles, there is little point in talking about various dynamo regimes. We need to fix one of the key unknowns!
Abstracts
Please send your abstracts to Rainer Arlt (rarlt@aip.de) by April 30, 2012. We are looking forward to your contributions!
Talks proposed:
-
Jérome Bouvier: Angular momentum evolution models and their predictions regarding tachocline differential rotation in solar-type stars
- Matthew Browning: Simulations of differential rotation on very low mass stars and its quenching by magnetic fields
- Allan Sacha Brun: Direct simulations of differential rotation
- Enrico Corsaro: Differential-rotation reconstruction through Bayesian inference
- Olivier Do Cao: On cycle modulations and torsional oscillations in dynamo models of solar-like stars
- Manuel Flores Soriano: Surface velocity fields on LQ Hya and XX Tri
- Rafael García: Asteroseismic prospects for measuring differential rotation
- Manfred Küker: Theory of differential rotation along the lower main sequence
- Stephen Marsden: Differential rotation of young solar-type stars
- Timo Reinhold: Observed differential rotation on very low-mass stars
