Swinburne
Browse

The anatomy of the NGC 5044 group - II. Stellar populations and star formation histories

Download (931.33 kB)
journal contribution
posted on 2024-07-26, 14:13 authored by J. Trevor Mendel, Robert N. Proctor, Jesper Rasmussen, Sarah Brough, Duncan ForbesDuncan Forbes
The distribution of galaxy properties in groups and clusters holds important information on galaxy evolution and growth of structure in the Universe. While clusters have received appreciable attention in this regard, the role of groups as fundamental to formation of the present-day galaxy population has remained relatively unaddressed. Here, we present stellar ages, metallicities and α-element abundances derived using Lick indices for 67 spectroscopically confirmed members of the NGC 5044 galaxy group with the aim of shedding light on galaxy evolution in the context of the group environment. We find that galaxies in the NGC 5044 group show evidence for a strong relationship between stellar mass and metallicity, consistent with their counterparts in both higher and lower mass groups and clusters. Galaxies show no clear trend of age or α-element abundance with mass, but these data form a tight sequence when fitted simultaneously in age, metallicity and stellar mass. In the context of the group environment, our data support the tidal disruption of low-mass galaxies at small group-centric radii, as evident from an apparent lack of galaxies below ~109 M⊙ within ~100 kpc of the brightest group galaxy. Using a joint analysis of absorption- and emission-line metallicities, we are able to show that the star-forming galaxy population in the NGC 5044 group appears to require gas removal to explain the ~1.5 dex offset between absorption- and emission-line metallicities observed in some cases. A comparison with other stellar population properties suggests that this gas removal is dominated by galaxy interactions with the hot intragroup medium.

Funding

National Science Foundation

National Aeronautics and Space Administration

Australian Research Council

History

Available versions

PDF (Accepted manuscript)

ISSN

1365-2966

Journal title

Monthly Notices of the Royal Astronomical Society

Volume

396

Issue

4

Pagination

20 pp

Publisher

Wiley

Copyright statement

Copyright © 2009 The authors. Journal compilation Copyright © 2009 Royal Astronomical Society. The accepted manuscript is reproduced in accordance with the copyright policy of the publisher. The definitive version is available at www.interscience.wiley.com.

Notes

This publication makes use of data products from the 2MASS, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. The authors also thank the Australian Research Council for funding that supported this work.

Language

eng

Usage metrics

    Publications

    Categories

    No categories selected

    Keywords

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC