The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: modelling of the luminosity and colour dependence in the Data Release 10

Citation:

Guo H, Zheng Z, Zehavi I, Xu H, Eisenstein DJ, Weinberg DH, Bahcall NA, Berlind AA, Comparat J, McBride CK, et al. The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: modelling of the luminosity and colour dependence in the Data Release 10. Monthly Notices of the Royal Astronomical Society. 2014;441 :2398-2413.

Date Published:

July 1, 2014

Abstract:

We investigate the luminosity and colour dependence of clustering ofCMASS galaxies in the Sloan Digital Sky Survey-III Baryon OscillationSpectroscopic Survey Data Release 10, focusing on projected correlationfunctions of well-defined samples extracted from the full catalogue of˜540 000 galaxies at z ˜ 0.5 covering about 6500deg2. The halo occupation distribution framework is adoptedto model the measurements on small and intermediate scales (from 0.02 to60 h-1 Mpc), infer the connection of galaxies to dark matterhaloes and interpret the observed trends. We find that luminous redgalaxies in CMASS reside in massive haloes of mass M ˜1013-1014 h-1 M andmore luminous galaxies are more clustered and hosted by more massivehaloes. The strong small-scale clustering requires a fraction of thesegalaxies to be satellites in massive haloes, with the fraction at thelevel of 5-8 per cent and decreasing with luminosity. The characteristicmass of a halo hosting on average one satellite galaxy above aluminosity threshold is about a factor of 8.7 larger than that of a halohosting a central galaxy above the same threshold. At a fixedluminosity, progressively redder galaxies are more strongly clustered onsmall scales, which can be explained by having a larger fraction ofthese galaxies in the form of satellites in massive haloes. Ourclustering measurements on scales below 0.4 h-1 Mpc allow usto study the small-scale spatial distribution of satellites insidehaloes. While the clustering of luminosity-threshold samples can be welldescribed by a Navarro-Frenk-White profile, that of the reddest galaxiesprefers a steeper or more concentrated profile. Finally, we also usegalaxy samples of constant number density at different redshifts tostudy the evolution of luminous red galaxies, and find the clustering tobe consistent with passive evolution in the redshift range of 0.5 ≲z ≲ 0.6.

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