GaBoDS: The Garching-Bonn Deep Survey: VI. Cosmic shear analysis
Abstract
Aims. We present a cosmic shear analysis and data validation of 15 square degree high-quality R-band data of the Garching-Bonn Deep Survey obtained with the Wide Field Imager of the MPG/ESO 2.2m telescope. Methods. We measure the two-point shear correlation functions to calculate the aperture mass dispersion. Both statistics are used to perform the data quality control. Combining the cosmic shear signal with a photometric redshift distribution of a galaxy sub-sample obtained from two square degree of UBVRI-band observations of the Deep Public Survey we determine constraints for the matter density Omega_m, the mass power spectrum normalisation sigma_8 and the dark energy density Omega_Lambda in the magnitude interval R in [21.5,24.5]. In this magnitude interval the effective number density of source galaxies is n=12.5/sq. arcmin, and their mean redshift is z_m=0.78. To estimate the posterior likelihood we employ the Monte Carlo Markov Chain method. Results. Using the aperture mass dispersion we obtain for the mass power spectrum normalisation sigma_8=0.80 +- 0.10 (1 sigma statistical error) at a fixed matter density Omega_m=0.30 assuming a flat universe with negligible baryon content and marginalising over the Hubble parameter and the uncertainties in the fitted redshift distribution.
Keywords
Cite
@article{arxiv.astro-ph/0606571,
title = {GaBoDS: The Garching-Bonn Deep Survey: VI. Cosmic shear analysis},
author = {M. Hetterscheidt and P. Simon and M. Schirmer and H. Hildebrandt and T. Schrabback and T. Erben and P. Schneider},
journal= {arXiv preprint arXiv:astro-ph/0606571},
year = {2009}
}
Comments
23 pages, 19 figures, submitted to A&A