The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: the low redshift sample

Abstract: We report on the small scale (0.5<r<40h^-1 Mpc) clustering of 78895 massive (M*~10^11.3M_sun) galaxies at 0.2<z<0.4 from the first two years of data from the Baryon Oscillation Spectroscopic Survey (BOSS), to be released as part of SDSS Data Release 9 (DR9). We describe the sample selection, basic properties of the galaxies, and caveats for working with the data. We calculate the real- and redshift-space two-point correlation functions of these galaxies, fit these measurements using Halo Occupation Distribution (HOD) modeling within dark matter cosmological simulations, and estimate the errors using mock catalogs. These galaxies lie in massive halos, with a mean halo mass of 5.2x10^13 h^-1 M_sun, a large scale bias of ~2.0, and a satellite fraction of 12+/-2%. Thus, these galaxies occupy halos with average masses in between those of the higher redshift BOSS CMASS sample and the original SDSS I/II LRG sample.