Cluster mass profiles from weak lensing: The influence of substructure

¹ Institut für Astrophysik und Extraterrestrische Forschung der Universität Bonn, Auf dem Hügel 71, Bonn, Germany
² Max Planck Institut für Astrophysik, Karl-Schwarzschild Str 1, Garching bei München, Germany

Corresponding author: L. J. King, lindsay@astro.uni-bonn.de

Received: 13 June 2001
Accepted: 22 August 2001

Abstract

The tidal gravitational field of a cluster distorts the shapes of background galaxies. This signature can be used to place constraints on the mass profile of the cluster, using a maximum likelihood analysis to find the best-fit parameterised model. In Schneider et al. ([CITE]) and King & Schneider ([CITE]) we investigated how accurately parameters can be obtained, concentrating on smooth profiles. Here, we consider a realistic model for substructure in a cluster (from N-body simulations), in order to see what influence this has on the recovery of parameters. We find that for a typical cluster at , the presence of substructure increases the error on parameters recovered from weak lensing data by ≈3% . Even doubling the substructure amplitude induces only a ≈10% increase in the parameter dispersion: this bodes well for our method.