The power spectrum and bispectrum of SDSS DR11 BOSS galaxies  II. Cosmological interpretation
Abstract
We examine the cosmological implications of the measurements of the linear growth rate of cosmological structure obtained in a companion paper from the power spectrum and bispectrum monopoles of the Sloan Digital Sky Survey III Baryon Oscillation Spectroscopic Survey Data Release 11, CMASS galaxies. This measurement was of f ^{0.43}σ_{8}, where σ_{8} is the amplitude of dark matter density fluctuations, and f is the linear growth rate, at the effective redshift of the survey, z_{eff} = 0.57. In conjunction with cosmic microwave background (CMB) data, interesting constraints can be placed on models with nonstandard neutrino properties and models where gravity deviates from General Relativity on cosmological scales. In particular, the sum of the masses of the three species of the neutrinos is constrained to m_{ν} < 0.49 eV (at 95 per cent confidence level) when the f ^{0.43}σ_{8} measurement is combined with stateoftheart CMB measurements. Allowing the effective number of neutrinos to vary as a free parameter does not significantly change these results. When we combine the measurement of f ^{0.43}σ_{8} with the complementary measurement of fσ_{8} from the monopole and quadrupole of the twopoint correlation function, we are able to obtain an independent measurements of f and σ_{8}. We obtain f = 0.63 ± 0.16 and σ_{8} = 0.710 ± 0.086 (68 per cent confidence level). This is the first time when these parameters have been able to be measured independently using the redshiftspace power spectrum and bispectrum measurements from galaxy clustering data only.
 Publication:

Monthly Notices of the Royal Astronomical Society
 Pub Date:
 September 2015
 DOI:
 10.1093/mnras/stv1359
 arXiv:
 arXiv:1408.0027
 Bibcode:
 2015MNRAS.452.1914G
 Keywords:

 galaxies: haloes;
 cosmological parameters;
 cosmology: theory;
 largescale structure of Universe;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 Astrophysics  Astrophysics of Galaxies
 EPrint:
 9 pages, 5 figures, 1 table. Accepted for publication in MNRAS