2005/12/06 by Morad Masjedi, David W. Hogg, Richard J. Cool +8 · 3 citations
Engineering · Physics and Astronomy · #Astronomy and Astrophysical Research #Galaxies: Formation, Evolution, Phenomena #Space Technology and Applications #astro-ph
paper · pdf · doi:10.1086/503536
published as Astrophys.J.644:54-60,2006 · Submitted to ApJ
arxiv created 2005/12/06 · openalex publication_date 2006/06/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We present the small-scale (0.01 Mpc < r < 8 h -1 Mpc) projected correlation function w p ( r p ) and real-space correlation function ξ( r ) of 24,520 luminous early-type galaxies from the Sloan Digital Sky Survey (SDSS) Luminous Red Galaxy (LRG) sample (0.16 < z < 0.36). "Fiber collision" incompleteness of the SDSS spectroscopic sample at scales smaller than 55'' prevents measurements of the correlation function for LRGs on scales smaller than ~0.3 Mpc by the usual methods. In this work, we cross-correlate the spectroscopic sample with the imaging sample, with a weighting scheme to account for the collisions, extensively tested against mock catalogs. We correct for photometric biases in the SDSS imaging of close galaxy pairs. We find that the correlation function ξ( r ) is surprisingly close to a r -2 power law over more than 4 orders of magnitude in separation r . This result is too steep at small scales to be explained in current versions of the halo model for galaxy clustering. We infer an LRG-LRG merger rate of ≲0.6 × 10 4 Gyr -1 Gpc -3 for this sample. This result suggests that the LRG-LRG mergers are not the main mode of mass growth for LRGs at z < 0.36.