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Title: Optimizing weak lensing mass estimates for cluster profile uncertainty

Weak lensing measurements of cluster masses are necessary for calibrating mass-observable relations (MORs) to investigate the growth of structure and the properties of dark energy. However, the measured cluster shear signal varies at fixed mass M200m due to inherent ellipticity of background galaxies, intervening structures along the line of sight, and variations in the cluster structure due to scatter in concentrations, asphericity and substructure. We use N-body simulated halos to derive and evaluate a weak lensing circular aperture mass measurement Map that minimizes the mass estimate variance <(Map - M200m)2> in the presence of all these forms of variability. Depending on halo mass and observational conditions, the resulting mass estimator improves on Map filters optimized for circular NFW-profile clusters in the presence of uncorrelated large scale structure (LSS) about as much as the latter improve on an estimator that only minimizes the influence of shape noise. Optimizing for uncorrelated LSS while ignoring the variation of internal cluster structure puts too much weight on the profile near the cores of halos, and under some circumstances can even be worse than not accounting for LSS at all. As a result, we discuss the impact of variability in cluster structure and correlated structuresmore » on the design and performance of weak lensing surveys intended to calibrate cluster MORs.« less
Authors:
 [1] ;  [2] ;  [3] ;  [4]
  1. Univ. of Pennsylvania, Philadelphia, PA (United States); Univ. Observatory Munich, Munich (Germany)
  2. Univ. of Pennsylvania, Philadelphia, PA (United States)
  3. Univ. of Tokyo, Chiba (Japan)
  4. Univ. Observatory Munich, Munich (Germany); Max Planck Institute for Extraterrestrial Physics, Garching (Germany)
Publication Date:
OSTI Identifier:
1203605
Grant/Contract Number:
FG02-95ER40893
Type:
Accepted Manuscript
Journal Name:
Monthly Notices of the Royal Astronomical Society
Additional Journal Information:
Journal Volume: 416; Journal Issue: 2; Journal ID: ISSN 0035-8711
Publisher:
Royal Astronomical Society
Research Org:
Univ. of Pennsylvania, Philadelphia, PA (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS cluster profile uncertainty; gravitational lensing; weak galaxies; clusters; cosmology; observations