Fulltext

The star formation histories of low surface brightness galaxies

Bell, Eric F. ; Barnaby, David ; Bower, Richard G. ; de Jong, Roelof S. ; Harper, Doyal A. ; Hereld, Mark ; Loewenstein, Robert F. ; Rauscher, Bernard J.

In: Monthly Notices of the Royal Astronomical Society, 2000, vol. 312, no. 3, p. 470-496

Add to personal list
    Title
    • The star formation histories of low surface brightness galaxies
    Author
    • Bell, Eric F.. Science Labs, Department of Physics, University of Durham, South Road, Durham DH1 3LE
    • Barnaby, David. Yerkes Observatory, University of Chicago, 373 W Geneva St, Williams Bay, WI 53191, USA
    • Bower, Richard G.. Science Labs, Department of Physics, University of Durham, South Road, Durham DH1 3LE
    • de Jong, Roelof S.. Science Labs, Department of Physics, University of Durham, South Road, Durham DH1 3LE
    • Harper, Doyal A.. Yerkes Observatory, University of Chicago, 373 W Geneva St, Williams Bay, WI 53191, USA
    • Hereld, Mark. Department of Astronomy and Astrophysics, University of Chicago, 5640 S. Ellis Ave, Chicago, IL 60637, USA
    • Loewenstein, Robert F.. Yerkes Observatory, University of Chicago, 373 W Geneva St, Williams Bay, WI 53191, USA
    • Rauscher, Bernard J.. Science Labs, Department of Physics, University of Durham, South Road, Durham DH1 3LE
    Document Type
    • Postprint
    OAI-PMH Identifier
    • oai:doc.rero.ch:300255
    Summary
    We have performed deep imaging of a diverse sample of 26 low surface brightness galaxies (LSBGs) in the optical and the near-infrared. Using stellar population synthesis models, we find that it is possible to place constraints on the ratio of young to old stars (which we parametrize in terms of the average age of the galaxy), as well as the metallicity of the galaxy, using optical and near-infrared colours. LSBGs have a wide range of morphologies and stellar populations, ranging from older, high-metallicity earlier types to much younger and lower-metallicity late-type galaxies. Despite this wide range of star formation histories, we find that colour gradients are common in LSBGs. These are most naturally interpreted as gradients in mean stellar age, with the outer regions of LSBGs having lower ages than their inner regions. In an attempt to understand what drives the differences in LSBG stellar populations, we compare LSBG average ages and metallicities with their physical parameters. Strong correlations are seen between an LSBG's star formation history and its K-band surface brightness, K-band absolute magnitude and gas fraction. These correlations are consistent with a scenario in which the star formation history of an LSBG primarily correlates with its surface density and its metallicity correlates with both its mass and its surface density