Stellar Astrophysics: the power of simultaneous high resolution stellar spectroscopy, polarimetry and velocimetry. - Rotation, activity and stellar magnetic fields in the A0 standard star Vega

05.09.2019, 11:00-12:00  –  Campus Golm, Haus 9, Raum 0.12
SFB-Seminar

Torsten Böhm, Université de Toulouse

Neo-Narval at TBL/Pic du Midi (France) will be the first instrument working simultaneously in high resolution spectroscopy, polarimetry and velocimetry being entirely dedicated to stellar astrophysics.  I will show the power of such an astronomical equipment (first light in 10/2019), illustrated on quasi continuous spectroscopic time series of the A0 standard star Vega.

The detailed study of photospheric line profile variations enabled us to conclude on the stellar rotation period and the existence of activity tracing surface spots, providing a clear indication of the existence of a structured stellar surface, an intriguing fact in a star exempt of subphotospheric convection.