Constraints on Neutrino Masses from Weak Lensing

TL;DR

This paper uses weak lensing data combined with other cosmological measurements to constrain the total mass of neutrinos, improving limits significantly over previous bounds.

Contribution

It provides new neutrino mass constraints by combining weak lensing with WMAP5, SNe, and BAO data, accounting for non-Gaussian covariances in the analysis.

Findings

Upper bounds on neutrino masses are 1.1, 0.76, and 0.54 eV for different data combinations.

Weak lensing alone cannot tightly constrain neutrino masses due to parameter degeneracies.

Combining multiple cosmological probes significantly improves neutrino mass limits.

Abstract

The weak lensing (WL) distortions of distant galaxy images are sensitive to neutrino masses by probing the suppression effect on clustering strengths of total matter in large-scale structure. We use the latest measurement of WL correlations, the CFHTLS data, to explore constraints on neutrino masses. We find that, while the WL data alone cannot place a stringent limit on neutrino masses due to parameter degeneracies, the constraint can be significantly improved when combined with other cosmological probes, the WMAP 5-year (WMAP5) data and the distance measurements of type-Ia supernovae (SNe) and baryon acoustic oscillations (BAO). The upper bounds on the sum of neutrino masses are m_tot = 1.1, 0.76 and 0.54 eV (95% CL) for WL+WMAP5, WMAP5+SNe+BAO, and WL+WMAP5+SNe+BAO, respectively, assuming a flat LCDM model with finite-mass neutrinos. In deriving these constraints, our analysis includes the non-Gaussian covariances of the WL correlation functions to properly take into account significant correlations between different angles.