Matthias Ammler-von Eiff
CAUP

Abstract
The spectroscopic determination of chemical stellar abundances strongly relies on the  underlying stellar parameters, in particular effective temperature and surface gravity. These can be derived by spectroscopy from the wings of strong lines and the equivalent widths of weak lines. I will illustrate the use of the iron ionization equilibrium and the wings of Halpha in order to determine surface gravity and effective temperature.
The rectification of the relative continuum turns out a crucial pre-requisite which is illustrated by the application to the Halpha line of a very young star and a star harbouring a transiting extra-solar planet.

2009 February 25, 13:30

IA/U.Porto
Centro de Astrofísica da Universidade do Porto (Auditorium)
Rua das Estrelas, 4150-762 Porto