Departament d'Astronomia i Astrofísica
Universitat de València

    Absorption line indices for constraining galaxy formation scenarios

Alexandre Vazdekis

Instituto de Astrofísica de Canarias

Seminari del departament d'Astronomia i Astrofísica

Dimecres 31 març 2004



During the last decade absorption line-strenghts have allowed us to carry out a comprehensive analysis of stellar populations in nearby galaxies. This success is due to the fact that the effects of relevant stellar population parameters are selectively emphasized in several absorption features. Nowadays it turned out that stellar populations analyses are providing the strongest constraints to current galaxy formation scenarios. I will describe the main features of this approach pinpointing the most popular indices and diagnostic diagrams and the main problems affecting these studies such as the degeneracy between age and metallicity. A new modeling effort for predicting galaxy spectra at moderately high resolution will be presented as well as its advantage for breaking the fundamental degeneracies affecting the integrated light of the stellar populations. Accurate determination of relevant stellar population parameters of galaxies embedded in different environments will be shown. A special emphasis will be given to new abundance ratio relations as a function of environment and their impact on galaxy formation scenarios.