Optimal Weak Lensing Skewness Measurements

Abstract

Weak lensing measurements are entering a precision era to statistically map the distribution of matter in the universe. The most common measurement has been of the variance of the projected surface density of matter, which corresponds to the induced correlation in alignments of background galaxies. This measurement of the fluctuations is insensitive to the total mass content, like using waves on the ocean to measure its depths. But when the depth is shallow as happens near a beach, waves become skewed. Similarly, a measurement of skewness in the projected matter distribution directly measures the total matter content of the universe. While skewness has already been convincingly detected, its constraint on cosmology is still weak. We address optimal analyses for the CFHT Legacy Survey in the presence of noise. We show that a compensated Gaussian filter with a width of 2.5 arc minutes optimizes the cosmological constraint, yielding $\Delta {\Omega }_m/{\Omega }_m\sim 10$. This is significantly better than other filters which have been considered in the literature. This can be further improved with tomography and other sophisticated analyses.

19 pages including 6 figures and 1 table, accepted for publication in ApJ, minor revisions

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Cited by in corpus (21)

• Weak Gravitational Lensing
• Intrinsic alignment-lensing interference as a contaminant of cosmic shear
• Gravitational Lensing
• The Skewness of the Aperture Mass Statistic
• Information content of weak lensing power spectrum and bispectrum: including the non-Gaussian error covariance matrix
• Breaking degeneracies in modified gravity with higher (than 2nd) order weak-lensing statistics
• The Weak Lensing Bispectrum
• Cosmological constraints from the capture of non-Gaussianity in Weak Lensing data
• Breaking the Degeneracy: Optimal Use of Three-point Weak Lensing Statistics
• The covariance of cosmic shear correlation functions and cosmological parameter estimates using redshift information
• On the estimation of gravity-induced non-Gaussianities from weak lensing surveys
• Fast Calculation of the Weak Lensing Aperture Mass Statistic
• Cusp-core problem and strong gravitational lensing
• Information Content in the Angular Power Spectrum of Weak Lensing: Wavelet Method
• Nonsingular density profiles of dark matter halos and Strong gravitational lensing
• The non-linear evolution of bispectrum from the scale-free N-body simulation
• The Weak Lensing Peak Statistics in the Mocks by the inverse-Gaussianization Method
• Reconstruction of the One-point Distribution of Convergence from Weak Lensing by Large-scale Structure
• Optimizing the Recovery of Fisher Information in the Dark Matter Power Spectrum
• Strong Lensing Probabilities in a Cosmological Model with a Running Primordial Power Spectrum
• The Mass Function of Dark Matter Haloes in a Cosmological Model with a Running Primordial Power Spectrum