2007/10/16 by Ignacio Ferreras, Prasenjit Saha, Scott Burles
Environmental Science · Physics and Astronomy · #Galaxies: Formation, Evolution, Phenomena #Impact of Light on Environment and Health #Remote Sensing in Agriculture #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2007.12606.x
published as Mon.Not.Roy.Astron.Soc. 383 (2008) 857-863 · 8 pages, 7 figures. Accepted for publication in MNRAS
arxiv created 2007/10/16 · openalex publication_date 2007/12/07 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
We present a spatially resolved comparison of the stellar mass and total mass surface distributions of nine early-type galaxies. The galaxies are a subset of the Sloan Lens ACS Survey. The total mass distributions are obtained by exploring pixelated mass models that reproduce the lensed images. The stellar mass distributions are derived from population-synthesis models fit to the photometry of the lensing galaxies. Uncertainties – mainly model degeneracies – are also computed. Stars can account for all the mass in the inner regions. A Salpeter initial mass function actually gives too much stellar mass in the inner regions and hence appears ruled out. Dark matter becomes significant by the half-light radius and becomes increasingly dominant at larger radii. The stellar and dark components are closely aligned, but the actual ellipticities are not correlated. Finally, we attempt to intuitively summarize the results by rendering the density, stellar versus dark ratio, and uncertainties as false-colour maps.