Model stars for the modelling of galaxies: $α$-enhancement in stellar populations models

Abstract

Stellar population (SP) models are an essential tool to understand the observations of galaxies and clusters. One of the main ingredients of a SP model is a library of stellar spectra, and both empirical and theoretical libraries can been used for this purpose. Here I will start by giving a short overview of the pros and cons of using theoretical libraries, i.e. model stars, to produce our galaxy models. Then I will address the question on how theoretical libraries can be used to model stellar populations, in particular to explore the effect of $α$-enhancement on spectral observables.

Invited contribution to the XII Latin American IAU Regional Meeting, Isla Margarita, Venezuela. To appear in "Memorias de la Reunion Regional Latino Americana de la UAI (2007)"