Weighing Neutrinos: Weak Lensing Approach

Abstract

We study the possibility for a measurement of neutrino mass using weak gravitational lensing. The presence of non-zero mass neutrinos leads to a suppression of power at small scales and reduces the expected weak lensing signal. The measurement of such a suppression in the weak lensing power spectrum allows a direct measurement of the neutrino mass, in contrast to various other experiments which only allow mass splittings between two neutrino species. Making reasonable assumptions on the accuracy of cosmological parameters, we suggest that a weak lensing survey of 100 sqr. degrees can be easily used to detect neutrinos down to a mass limit of 3.5 eV at the 2 sigma level. This limit is lower than current limits on neutrino mass, such as from the Ly-alpha forest and SN1987A. An ultimate weak lensing survey of pi steradians down to a magnitude limit of 25 can be used to detect neutrinos down to a mass limit of 0.4 eV at the 2 sigma level, provided that other cosmological parameters will be known to an accuracy expected from cosmic microwave background spectrum using the MAP satellite. With improved parameters estimated from the PLANCK satellite, the limit on neutrino mass from weak lensing can be further lowered by another factor of 3 to 4. For much smaller surveys (10 sqr. degrees) that are likely to be first available in the near future with several wide-field cameras, the presence of neutrinos can be safely ignored when deriving conventional cosmological parameters such as the mass density of the Universe. However, armed with cosmological parameter estimates with other techniques, even such small area surveys allow a strong possibility to investigate the presence of non-zero mass neutrinos.

8 pages + 3 figures, accepted version. A&A (in press)

Cited by in corpus (19)

• Weak Gravitational Lensing
• Halo Models of Large Scale Structure
• Neutrino Physics from the Cosmic Microwave Background and Large Scale Structure
• Inflation Physics from the Cosmic Microwave Background and Large Scale Structure
• Neutrino Mass Ordering from Oscillations and Beyond: 2018 Status and Future Prospects
• Cosmological and Astrophysical Neutrino Mass Measurements
• Probing neutrino masses with CMB lensing extraction
• Constraints on Neutrino Masses from Weak Lensing
• Gravitational Lensing of Epoch-of-reionization Gas
• Dark Energy and Neutrino Masses from Future Measurements of the Expansion History and Growth of Structure
• A Multi-Parameter Investigation of Gravitational Slip
• Neutrino mass from future high redshift galaxy surveys: sensitivity and detection threshold
• Observational constraints on cosmic neutrinos and dark energy revisited
• Cosmological Implications of Neutrinos
• Constraints on Neutrino Mass and Light Degrees of Freedom in Extended Cosmological Parameter Spaces
• Anisotropies in the Cosmic Neutrino Background after WMAP 5-year Data
• Gravitational Lensing of Supernova Neutrinos
• Future constraints on variations of the fine structure constant from combined CMB and weak lensing measurements
• Cosmological Implications of a Neutrino Mass Detection