Can Sterile Neutrino Explain Very High Energy Photons from GRB221009A?

TL;DR

This paper investigates whether sterile neutrinos could explain the extremely high energy photons observed from GRB221009A, but finds that standard cosmological constraints strongly disfavor this hypothesis.

Contribution

The study evaluates the sterile neutrino explanation for high-energy photons from GRB221009A and demonstrates its incompatibility with CMB and BBN constraints in standard cosmology.

Findings

Sterile neutrino explanation is disfavored by CMB constraints.

Sterile neutrino explanation is disfavored by BBN constraints.

Standard cosmology rules out sterile neutrino as source of high-energy photons.

Abstract

The LHAASO collaboration has reported their observation of very high energy photons ($E^{max}_\gamma \simeq 18$ TeV) from the gamma-ray burst GRB221009A. The sterile neutrino that involves both mixing and transition magnetic moment may be a viable explanation for these high energy photon events. However, we demonstrate that such a solution is strongly disfavored by the cosmic microwave background (CMB) and Big Bang nucleosynthesis (BBN) in the standard cosmology.