Constraints on neutrino-Majoron couplings using SN1987A data

TL;DR

This paper uses SN1987A neutrino data and supernova simulations to set new bounds on neutrino-Majoron couplings, impacting theories of neutrino decay and dark matter.

Contribution

First likelihood analysis of SN1987A neutrino data incorporating neutrino decay to Majorons within a three-neutrino framework.

Findings

Established bounds on neutrino-Majoron couplings.

Demonstrated spectral distortions constrain new physics.

Provided bounds competitive with existing limits.

Abstract

Neutrino decay to a lighter neutrino and a massless or almost massless (pseudo)scalar Goldstone boson remains of wide interest, as in the search for ultralight dark matter or for neutrinoless double beta-decay, and for its implications in astrophysics and cosmology. Neutrino interactions with Majorons can affect the dynamics of supernovae and impact the emitted neutrino flux. Using a three-neutrino framework and detailed supernova simulations, we perform the first likelihood analysis of the 24 neutrino events from SN1987A, including nonradiative decay in matter to a massless (pseudo)scalar boson like a Majoron. Focusing on the induced spectral distortions, we present bounds on the neutrino-Majoron couplings, as a function of the lightest neutrino mass, that are either complementary or competitive with current ones.