2008/07/22 by T. D. Rawle, Russell J. Smith, J. R. Lucey +1 · 44 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy cluster #Luminosity #Metallicity #Population #Radial velocity #Spectrograph #Stellar population #Stellar, planetary, and galactic studies #Surface brightness fluctuation #Velocity dispersion #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2008.13720.x
published in Monthly Notices of the Royal Astronomical Society 389(4), 1891-1904 (Oxford University Press) · 14 pages, 15 figures. Accepted by MNRAS
arxiv created 2008/07/22 · openalex publication_date 2008/09/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present results from a pilot study of radial stellar population trends in early-type galaxies using the Very Large Telescope (VLT) Visible Multi-Object Spectrograph (VIMOS) integral field unit (IFU). We observe 12 galaxies in the cluster Abell 3389 (z≈ 0.027). For each galaxy, we measure 22 line strength indices in multiple radial bins out to at least the effective radius. We derive stellar population parameters using a grid inversion technique, and calculate the radial gradients in age, metallicity and α-abundance. Generally, the galaxies in our sample have flat radial trends in age and [α/Fe], but negative gradients in [Z/H] (−0.20 ± 0.05 dex). Combining our targets with two similar, long-slit studies to increase sample size, we find that the gradients are not correlated with the central velocity dispersion or K-band luminosity (both proxies for galaxy mass). However, we find that the age and metallicity gradients are both anticorrelated with their respective central values (to >4σ), such that galaxies with young cores have steeper positive age gradients, and those with metal-rich centres have strong negative [Z/H] gradients.