Multipole analysis of redshift-space distortions around cosmic voids

Hamaus, Nico; Cousinou, Marie-Claude; Pisani, Alice; Aubert, Marie; Escoffier, Stephanie und Weller, Jochen (2017): Multipole analysis of redshift-space distortions around cosmic voids. In: Journal of Cosmology and Astroparticle Physics, Nr. 7, 14

Abstract

We perform a comprehensive redshift-space distortion analysis based on cosmic voids in the large-scale distribution of galaxies observed with the Sloan Digital Sky Survey. To this end, we measure multipoles of the void-galaxy cross-correlation function and compare them with standard model predictions in cosmology. Merely considering linear-order theory allows us to accurately describe the data on the entire available range of scales and to probe void-centric distances down to about 2 h(-1) Mpc. Common systematics, such as the Fingers-of-God effect, scale-dependent galaxy bias, and nonlinear clustering do not seem to play a significant role in our analysis. We constrain the growth rate of structure via the redshift-space distortion parameter beta at two median redshifts, beta (z = 0 : 32) = 0.599(-0.124)(+0.134) and beta(z = 0 : 54) = 0.457(- 0.054)(+ 0.056) , with a precision that is competitive with state-of-the-art galaxy-clustering results. While the high-redshift constraint perfectly agrees with model expectations, we observe a mild 2 sigma deviation at z = 0.32, which increases to 3 sigma when the data is restricted to the lowest available redshift range of 0.15 < z < 0.33.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik > Astronomie und Astrophysik, Kosmologie
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 1475-7516
• Sprache: Englisch