An Optimized H_β Index for Disentangling Stellar Clusters and Galaxy Ages

Cervantes-Rodriguez, J. L.; Vazdekis, A.
Bibliographical reference

From Stars to Galaxies: Building the Pieces to Build Up the Universe. ASP Conference Series, Vol. 374, proceedings of the conference held 16-20 October 2006 at Istituto Veneto di Scienze, Lettere ed Arti, Venice, Italy. Edited by Antonella Vallenari, Rosaria Tantalo, Laura Portinari, and Alessia Moretti., p.405

Advertised on:
12
2007
Number of authors
2
IAC number of authors
0
Citations
0
Refereed citations
0
Description
We have derived a new H_{β} absorption index definition, which is fully optimized as an age indicator for old and intermediate-aged stellar populations. Rather than using stellar spectra, we employed theoretical SEDs at moderately high resolution for simple stellar populations of different ages and metallicities. The new index, which is virtually insensitive to metallicity, provides us with improved abilities for lifting the age-metallicity degeneracy, that affects the standard H_{β} Lick/IDS index definition. Among other advantages this new index does not require spectra of extremely high signal-to-noise and it can be easily applied to observations of faint galaxies or surveys data.