Cluster mass profile reconstruction with size and flux magnification on the HST STAGES survey

Christopher A J Duncan; Catherine Heymans; Alan F Heavens; Benjamin Joachimi

doi:10.1093/mnras/stw027

Cluster mass profile reconstruction with size and flux magnification on the HST STAGES survey

Mon Not R Astron Soc. 2016 Jan 23;457(1):764-785. doi: 10.1093/mnras/stw027. eCollection 2016 Mar 21.

Authors

Christopher A J Duncan¹, Catherine Heymans¹, Alan F Heavens², Benjamin Joachimi³

Affiliations

¹ Scottish Universities Physics Alliance, Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK.
² Imperial Centre for Inference and Cosmology, Department of Physics, Imperial College London, Blackett Laboratory, Prince Consort Road, London SW7 2AZ, UK.
³ Department of Physics and Astronomy, University College London, Gower Place, London WC1E 6BT, UK.

PMID: 27274702
DOI: 10.1093/mnras/stw027

Abstract

We present the first measurement of individual cluster mass estimates using weak lensing size and flux magnification. Using data from the HST STAGES (Space Telescope A901/902 Galaxy Evolution Survey) survey of the A901/902 supercluster we detect the four known groups in the supercluster at high significance using magnification alone. We discuss the application of a fully Bayesian inference analysis, and investigate a broad range of potential systematics in the application of the method. We compare our results to a previous weak lensing shear analysis of the same field finding the recovered signal-to-noise of our magnification-only analysis to range from 45 to 110 per cent of the signal-to-noise in the shear-only analysis. On a case-by-case basis we find consistent magnification and shear constraints on cluster virial radius, and finding that for the full sample, magnification constraints to be a factor 0.77 ± 0.18 lower than the shear measurements.

Keywords: dark matter; galaxies: clusters: general; gravitational lensing: weak; methods: data analysis.