The clustering of massive galaxies at z ∼ 0.5 from the first semester of BOSS data

We calculate the real-and redshift-space clustering of massive galaxies at z ∼ 0.5 using the first semester of data by the Baryon Oscillation Spectroscopic Survey (BOSS). We study the correlation functions of a sample of 44,000 massive galaxies in the redshift range 0.4 < z < 0.7. We present a halo-occupation distribution modeling of the clustering results and discuss the implications for the manner in which massive galaxies at z ∼ 0.5 occupy dark matter halos. The majority of our galaxies are central galaxies living in halos of mass 10¹³ h^-1 M_⊙, but 10% are satellites living in halos 10 times more massive. These results are broadly in agreement with earlier investigations of massive galaxies at z ∼ 0.5. The inferred large-scale bias (b ≈ 2) and relatively high number density (n̄ = 3 × 10-⁴ h³ Mpc^-3) imply that BOSS galaxies are excellent tracers of large-scale structure, suggesting BOSS will enable a wide range of investigations on the distance scale, the growth of large-scale structure, massive galaxy evolution, and other topics.