Reexamination of a Bound on the Dirac Neutrino Magnetic Moment from the Supernova Neutrino Luminosity

TL;DR

This paper reevaluates the upper bounds on the Dirac neutrino magnetic moment by considering realistic supernova core models and their impact on neutrino emission and cooling times.

Contribution

It introduces a more realistic modeling of supernova cores to refine bounds on neutrino magnetic moments based on neutrino emission effects.

Findings

New upper limits on the Dirac neutrino magnetic moment are established.

Realistic supernova models alter previous bounds derived from simplified assumptions.

The influence of right-handed neutrino emission on supernova cooling is quantitatively assessed.

Abstract

We investigate the neutrino helicity-flip process under supernova core conditions, where the left-handed neutrinos being produced can be converted into right-handed neutrinos sterile with respect to the weak interaction due to the interaction of magnetic moments with plasma electrons and protons. Instead of the uniform ball model for the SN core used in previous analyses, realistic models for radial distributions and time evolution of physical parameters in the supernova core are considered. We have obtained new upper limits on the Dirac neutrino magnetic moment averaged over flavours and time from the condition that the influence of the right-handed neutrino emission on the total cooling time scale should be limited.