Cosmological measurement of neutrino mass in the presence of leptonic asymmetry

TL;DR

This paper demonstrates that a small neutrino mass, consistent with existing data, can be detected through cosmological observations if a relic neutrino asymmetry exists, significantly impacting neutrino physics understanding.

Contribution

It shows that cosmological data can measure neutrino masses as low as 0.07 eV in the presence of relic asymmetry, highlighting the importance of neutrino asymmetry in cosmological models.

Findings

A 0.07 eV neutrino mass can be detected with future cosmological data.

Relic neutrino asymmetry enhances the detectability of neutrino mass.

Such measurements are crucial for understanding neutrino properties.

Abstract

We show that even the smallest neutrino mass consistent with the Super--Kamiokande data is relevant for cosmological models of structure formation and cosmic microwave background (CMB) anisotropies, provided that a relic neutrino asymmetry exists. We calculate the precision with which a 0.07 eV neutrino mass could be extracted from CMB anisotropy and large-scale structure data by the future Planck satellite and Sloan Digital Sky Survey. We find that such a mass can be detected, assuming a large relic neutrino asymmetry still allowed by current experimental data. This measurement of the absolute value of the neutrino mass would be crucial for our understanding of neutrino models.