Cosmological Tests using Redshift Space Clustering in BOSS DR11

  • Song, Yong-Seon (Korea Astronomy and Space Science Institute) ;
  • Sabiu, Cristiano G. (Korea Astronomy and Space Science Institute) ;
  • Okumura, Teppei (Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU, WPI)) ;
  • Oh, Minji (Korea Astronomy and Space Science Institute) ;
  • Linder, Eric V. (Korea Astronomy and Space Science Institute)
  • Published : 2015.04.10

Abstract

We analyze the clustering of large scale structure in the Universe in a model independent method, accounting for anisotropic effects along and transverse to the line of sight. A large sample of 690,000 galaxies from The Baryon Oscillation Spectroscopy Survey Data Release 11 are used to determine the Hubble expansion H, angular distance D_A, and growth rate GT at an effective redshift of z=0.57. After careful bias and convergence studies of the effects from small scale clustering, we find that cutting transverse separations below 40 Mpc/h delivers robust results while smaller scale data leads to a bias due to unmodelled nonlinear and velocity effects. The converged results are in agreement with concordance LCDM cosmology, general relativity, and minimal neutrino mass, all within the $68{\backslash}%$ confidence level. We also present results separately for the northern and southern hemisphere sky, finding a slight tension in the growth rate -- potentially a signature of anisotropic stress, or just covariance with small scale velocities -- but within $68{\backslash}%$ CL.

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