Evolution of the dark matter distribution with three-dimensional weak lensing

Abstract

We present a direct detection of the growth of large-scale structure, using weak gravitational lensing and photometric redshift data from the {COMBO-17} survey. We use deep R-band imaging of two 0.5 ?? 0.5 deg2 fields, affording shear estimates for over 52000 galaxies; we combine these with photometric redshift estimates from our 17-band survey, in order to obtain a {3D} shear field. We find theoretical models for evolving matter power spectra and correlation functions, and fit the corresponding shear correlation functions to the data as a function of redshift. We detect the evolution of the power at the 4.7?? level given reasonable priors, and measure the rate of evolution for 0 {\textless} z {\textless} 1. We also fit correlation functions to our {3D} data as a function of cosmological parameters ??8 and ????. We find joint constraints on ???? and ??8, demonstrating an improvement in accuracy by {\textasciitilde}=40 per cent over that available from {2D} weak lensing for the same area.