Journal Article

Stellar population trends in S0 galaxies

L. C. Prochaska Chamberlain, Stéphane Courteau, Michael McDonald and James A. Rose

in Monthly Notices of the Royal Astronomical Society

Published on behalf of The Royal Astronomical Society

Volume 412, issue 1, pages 423-447
Published in print March 2011 | ISSN: 0035-8711
Published online March 2011 | e-ISSN: 1365-2966 | DOI: http://dx.doi.org/10.1111/j.1365-2966.2010.17910.x
Stellar population trends in S0 galaxies

More Like This

Show all results sharing this subject:

  • Astronomy and Astrophysics

GO

Show Summary Details

Preview

We present stellar population age and metallicity trends for a sample of 59 S0 galaxies based on optical Sloan Digital Sky Survey (SDSS) and near-infrared (NIR) J and H photometry. When combined with optical g and r passband imaging data from the SDSS archive and stellar population models, we obtain radial age and metallicity trends out to at least five effective radii for most of the galaxies in our sample. The sample covers a range in stellar mass and light concentration. We find an average central light-weighted age of ∼4 Gyr and central metallicity [Z/H]∼ 0.2 dex. Almost all galaxies show a negative metallicity gradient from the centre out, with an average value of Δ[Z/H]/Δlog (r/Re) =−0.6. An age increase, decrease and minimal change with radius is observed for 58 per cent, 19 per cent and 23 per cent, respectively, for a mean age gradient of Δage/Δlog (r/Re) = 2.3 Gyr dex−1. For 14 out of 59 galaxies, the light-weighted age of the outer region is greater than 10 Gyr. We find that galaxies with both lower mass and lower concentration have younger light-weighted ages and lower light-weighted metallicities. This mass–metallicity relation extends into the outer regions of our S0 galaxies. Our results are consistent with the formation of S0 galaxies through the transformation of spiral galaxy discs. Determining the structural component that makes up the outer region of galaxies with old outskirts is a necessary step to understand the formation history of S0 galaxies.

Keywords: galaxies: elliptical and lenticular, cD; galaxies: evolution; galaxies: formation; galaxies: photometry

Journal Article.  18177 words.  Illustrated.

Subjects: Astronomy and Astrophysics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.