Effect of Measurement Errors on Predicted Cosmological Constraints from Shear Peak Statistics with LSST

TL;DR

This study evaluates how galaxy shape measurement errors affect the ability of shear peak statistics from LSST data to constrain cosmological models, finding minimal impact from these errors.

Contribution

It introduces the first analysis of measurement errors on galaxy shapes in shear peak statistics for LSST, using realistic simulations.

Findings

Measurement errors have limited impact on shear peak constraints.

Shear peak statistics remain robust despite shape measurement uncertainties.

The methodology combines LSST simulations with cosmological models.

Abstract

The statistics of peak counts in reconstructed shear maps contain information beyond the power spectrum, and can improve cosmological constraints from measurements of the power spectrum alone if systematic errors can be controlled. We study the effect of galaxy shape measurement errors on predicted cosmological constraints from the statistics of shear peak counts with the Large Synoptic Survey Telescope (LSST). We use the LSST image simulator in combination with cosmological N-body simulations to model realistic shear maps for different cosmological models. We include both galaxy shape noise and, for the first time, measurement errors on galaxy shapes. We find that the measurement errors considered have relatively little impact on the constraining power of shear peak counts for LSST.