The Gemini/Hubble Space Telescope Galaxy Cluster Project: Stellar Populations in the Low-redshift Reference Cluster Galaxies
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Jørgensen_2018_AJ_156_224.pdf
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Univ Arizona, Steward ObservIssue Date
2018-11Keywords
galaxies: clusters: individual (Abell 1656/Coma, Abell 426/Perseus, Abell 2029, Abell 2142)galaxies: evolution
galaxies: stellar content
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IOP PUBLISHING LTDCitation
Inger Jørgensen et al 2018 AJ 156 224Journal
ASTRONOMICAL JOURNALRights
© 2018. The American Astronomical Society. All rights reserved.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
In order to study stellar populations and galaxy structures at intermediate and high redshift (z = 0.2-2.0) and link these properties to those of low-redshift galaxies, there is a need for well-defined local reference samples. Especially for galaxies in massive clusters, such samples are often limited to the Coma cluster galaxies. We present consistently calibrated velocity dispersions and absorption-line indices for galaxies in the central 2 R-500 x 2 R-500 of four massive clusters at z < 0.1: Abell 426/Perseus, Abell 1656/Coma, Abell 2029, and Abell 2142. The measurements are based on data from the Gemini Observatory, McDonald Observatory, and Sloan Digital Sky Survey. For bulge-dominated galaxies, the samples are 95% complete in Perseus and Coma and 74% complete in A2029 and A2142, to a limit of M-B,M-abs <= -18.5 mag. The data serve as the local reference for our studies of galaxy populations in the higher-redshift clusters that are part of the Gemini/HST Galaxy Cluster Project (GCP). We establish the scaling relations between line indices and velocity dispersions as a reference for the GCP. We derive stellar population parameters, ages, metallicities [M/H], and abundance ratios from line indices, both averaged in bins of velocity dispersion and from individual measurements for galaxies in Perseus and Coma. The zero points of relations between the stellar population parameters and the velocity dispersions limit the allowed cluster-to-cluster variation of the four clusters to +/- 0.08 dex in age, +/- 0.06 dex in [M/H], +/- 0.07 dex in [CN/Fe], and +/- 0.03 dex in [Mg/Fe].ISSN
1538-3881Version
Final published versionSponsors
Alfred P. Sloan Foundation; U.S. Department of Energy Office of ScienceAdditional Links
http://stacks.iop.org/1538-3881/156/i=5/a=224?key=crossref.cd44433a4a0f0464bdcb2454850879aeScopus Count
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