Propagating Residual Biases in Cosmic Shear Power Spectra
Abstract
In this paper we derive a full expression for the propagation of multiplicative and additive shape measurement biases into the cosmic shear power spectrum. In doing so we identify several new terms that are associated with selection effects, as well as crosscorrelation terms between the multiplicative and additive biases and the shear field. The computation of the resulting bias in the shear power spectrum scales as the fifth power of the maximum multipole considered. Consequently the calculation is unfeasible for large lmodes, and the only tractable way to assess the full impact of shape measurement biases on cosmic shear power spectrum is through forward modelling of the effects. To linear order in bias parameters the shear power spectrum is only affected by the mean of the multiplicative bias field over a survey and the cross correlation between the additive bias field and the shear field. If the mean multiplicative bias is zero then second order convolutive terms are expected to be orders of magnitude smaller.
 Publication:

The Open Journal of Astrophysics
 Pub Date:
 July 2019
 DOI:
 10.21105/astro.1904.07173
 arXiv:
 arXiv:1904.07173
 Bibcode:
 2019OJAp....2E...5K
 Keywords:

 galaxy bias;
 cosmology;
 largescale structure of the Universe;
 multipole expansion;
 weak gravitational lensing;
 cosmic shear;
 Astrophysics  Cosmology and Nongalactic Astrophysics
 EPrint:
 10 pages, accepted to the Open Journal of Astrophysics