Ages, metallicities and alpha-element enhancemen for galaxies in hickson compact groups.

• Grant number: 05/03928-8
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: November 01, 2005
• End date: January 31, 2006
• Field of knowledge: Physical Sciences and Mathematics - Astronomy - Extragalactic Astrophysics
• Principal Investigator: Claudia Lucia Mendes de Oliveira
• Grantee: Claudia Lucia Mendes de Oliveira
• Host Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Central velocity dispersions and eight line-strength Lick indices have been determined from long-slit spectra of 16 elliptical galaxies in Hickson compact groups. These data were used to determine galaxy properties (ages, metallicities and alpha-element enhancements) in compact groups and allowed a comparison with the parameters determined for a sample of galaxies in lower density environments, studied by Gonz\'alez (1993). Our main result is that the majority of the galaxies in compact groups seem to be old (median age of 14 Gyr for eight galaxies for which ages could be derived). (AU)