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Title: Tracing the cosmic velocity field at z∼ 0.1 from galaxy luminosities in the SDSS DR7

Spatial modulations in the distribution of observed luminosities (computed using redshifts) of ∼ 5× 10{sup 5} galaxies from the SDSS Data Release 7, probe the cosmic peculiar velocity field out to z∼ 0.1. Allowing for luminosity evolution, the r-band luminosity function, determined via a spline-based estimator, is well represented by a Schechter form with M{sup *}(z)-5 log{sub 10} h = -20.52 -1.6(z-0.1)± 0.05 and α{sup *} = -1.1± 0.03. Bulk flows and higher velocity moments in two redshift bins, 0.02 < z < 0.07 and 0.07 < z < 0.22, agree with the predictions of the ΛCDM model, as obtained from mock galaxy catalogs designed to match the observations. Assuming a ΛCDM model, we estimate σ{sub 8} ≈ 1.1± 0.4 for the amplitude of the linear matter power spectrum, where the low accuracy is due to the limited number of galaxies. While the low z bin is robust against coherent photometric uncertainties, the bias of results from the second bin is consistent with the ∼1% magnitude tilt reported by the SDSS collaboration. The systematics are expected to have a significantly lower impact in future datasets with larger sky coverage and better photometric calibration.
Authors:
;  [1] ;  [2]
  1. Department of Physics, Israel Institute of Technology --- Technion, Haifa 32000 (Israel)
  2. Department of Physics, Università Roma Tre, Via della Vasca Navale 84, Rome 00146 (Italy)
Publication Date:
OSTI Identifier:
22375891
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2014; Journal Issue: 09; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; AMPLITUDES; CALIBRATION; CATALOGS; DATASETS; FORECASTING; FUNCTIONS; GALAXIES; LUMINOSITY; MATTER; MODULATION; PROBES; RED SHIFT; SKY