Spectroscopy of the Sun and stellar atmospheres
Stellar atmospheres form the basis for both stellar spectroscopy and the analyses of exoplanet atmospheres, whose properties are deduced as subtle differences to the spectra of their host stars. We are specifically studying the Sun, solar-type stars and luminous giants. Our research aims at understanding the physical processes defining and shaping stellar spectra.
IMAGE1: Modeled stellar surfaces: Intensity patterns develop during granular evolution on small sections of the surface of a 12,000 K white dwarf (left) and a 3,800 K red giant (right).
IMAGE 2: Properties of exoplanet atmospheres may be deduced during planetary transits by measuring subtle differences relative to the spectrum of the host star.
IMAGE 3: Spectra in the infrared wavelength region of cool giant stars. At the top, spectrum of the K-type giant Arcturus; the others are M-type stars close to the Galactic center. Such data are used to study the chemical evolution at particular locations in the Galaxy.