Spatially resolved kinematics and stellar populations of brightest cluster and group galaxies

S. Brough, Robert Proctor, Duncan A. Forbes, Warrick J. Couch, C. A. Collins, D. J. Burke, R. G. Mann

Research output: Contribution to journalArticlepeer-review

Abstract / Description of output

We present an examination of the kinematics and stellar populations of a sample of three brightest group galaxies (BGGs) and three brightest cluster galaxies (BCGs) in X-ray groups and clusters. We have obtained high signal-to-noise ratio Gemini/Gemini South Multi-Object Spectrograph (GMOS) long-slit spectra of these galaxies and use Lick indices to determine ages, metallicities and α-element abundance ratios out to at least their effective radii. We find that the BGGs and BCGs have very uniform masses, central ages and central metallicities. Examining the radial dependence of their stellar populations, we find no significant velocity dispersion, age, or α-enhancement gradients. However, we find a wide range of metallicity gradients, suggesting a variety of formation mechanisms. The range of metallicity gradients observed is surprising, given the homogeneous environment these galaxies probe and their uniform central stellar populations. However, our results are inconsistent with any single model of galaxy formation and emphasize the need for more theoretical understanding of both the origins of metallicity gradients and galaxy formation itself. We postulate two possible physical causes for the different formation mechanisms.
Original languageEnglish
Pages (from-to)1507-1530
JournalMonthly Notices of the Royal Astronomical Society
Publication statusPublished - 1 Jul 2007

Keywords / Materials (for Non-textual outputs)

  • galaxies: clusters: general
  • galaxies: elliptical and lenticular
  • cD
  • galaxies: evolution
  • galaxies: formation


Dive into the research topics of 'Spatially resolved kinematics and stellar populations of brightest cluster and group galaxies'. Together they form a unique fingerprint.

Cite this