NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-05-19 T01:40:22 PDT
Help | Comment | NED Home

For refcode 2006A&A...457..809S:
Retrieve 93 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by European Southern Observatory (ESO). Reproduced by permission
2006A&A...457..809S Stellar populations of early-type galaxies in different environments. II. Ages and metallicities Sanchez-Blazquez, P.; Gorgas, J.; Cardiel, N.; Gonzalez, J. J. Abstract. Aims. This is the second paper of a series devoted to the study of the stellar content of early-type galaxies. The goal of the series is to set constraints on the evolutionary status of these objects Methods: We use a new set of models that include an improved stellar library (MILES) to derive simple stellar population (SSP)-equivalent parameters in a sample of 98 early-type galaxies. The sample contains galaxies in the field, poor groups, and galaxies in the Virgo and Coma clusters. Results: We find that low-density environment galaxies span a larger range in SSP age and metallicity than their counterparts in high density environments, with a tendency for lower {sigma} galaxies to be younger. Early-type galaxies in low-density environments appear on average ~1.5 Gyr younger and more metal rich than their counterparts in high density environments. The sample of low-density environment galaxies shows an age-metallicity relation in which younger galaxies are found to be more metal rich, but only when metallicity is measured with a Fe-sensitive index. Conversely, there is no age-metallicity relation when the metallicity is measured with a Mg sensitive index. The mass-metallicity relation is only appreciable for the low-density environment galaxies when the metallicity is measured with a Mg-sensitive index, and not when the metallicity is measured with other indicators. On the contrary, this relation exists for the high-density environment galaxies independent of the indicator used to measure the metallicity. Conclusions: This suggests a dependence of the mass-metallicity relation on the environment of the galaxies. Our data favour a scenario in which galaxies in low density environments have suffered a more extended star formation history than the galaxies in the Coma cluster, which appear to host more homogenous stellar populations. Key words: galaxies: abundances, galaxies: elliptical and lenticular, cD, Galaxy: stellar content, Galaxy: formation
Retrieve 93 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home