Durham University

Department of Physics

Staff profile

Publication details for Prof Richard Massey

Massey, R., Rhodes, J., Refregier, A., Albert, J., Bacon, D., Bernstein, G., Ellis, R., Jain, B., McKay, T., Perlmutter, S. & Taylor, A. (2004). Weak lensing from space. II. Dark matter mapping. Astronomical journal 127(6): 3089-3101.

Author(s) from Durham

Abstract

We study the accuracy with which weak-lensing measurements could be made from a future space-based survey, predicting the subsequent precision of three-dimensional dark matter maps, projected two-dimensional dark matter maps, and mass-selected cluster catalogs. As a baseline, we use the instrumental specifications of the SuperNova/Acceleration Probe (SNAP) satellite. We first compute its sensitivity to weak lensing shear as a function of survey depth. Our predictions are based on detailed image simulations created using "shapelets," a complete and orthogonal parameterization of galaxy morphologies. We incorporate a realistic redshift distribution of source galaxies and calculate the average precision of photometric redshift recovery using the SNAP filter set to be Δz = 0.034. The high density of background galaxies resolved in a wide space-based survey allows projected dark matter maps with an rms sensitivity of 3% shear in 1 arcmin2 cells. This will be further improved using a proposed deep space-based survey, which will be able to detect isolated clusters using a three-dimensional lensing inversion technique with a 1 σ mass sensitivity of approximately 1013 M⊙ at z = 0.25. Weak-lensing measurements from space will thus be able to capture non-Gaussian features arising from gravitational instability and map out dark matter in the universe with unprecedented resolution.