Neutrino Origin of LHAASO's 18 TeV GRB221009A Photon

TL;DR

This paper proposes a novel neutrino-based explanation for the 18 TeV photon detected from GRB221009A, involving sterile neutrinos and non-standard cosmology, challenging conventional photon propagation models.

Contribution

It introduces a new neutrino mixing and transition magnetic moment portal mechanism to explain ultra-high-energy photons from gamma-ray bursts.

Findings

Sterile neutrino production via mixing is efficient.

Transition magnetic moments influence decay rates.

The scenario aligns with terrestrial constraints and suggests non-standard cosmology.

Abstract

LHAASO collaboration detected photons with energy above 10 TeV from the most recent gamma-ray burst (GRB), GRB221009A. Given the redshift of this event, $z\sim 0.15$, photons of such energy are expected to interact with the diffuse extragalactic background light (EBL) well before reaching Earth. In this paper we provide a novel neutrino-related explanation of the most energetic 18 TeV event reported by LHAASO. We find that the minimal viable scenario involves both mixing and transition magnetic moment portal between light and sterile neutrinos. The production of sterile neutrinos occurs efficiently via mixing while the transition magnetic moment portal governs the decay rate in the parameter space where tree-level decays via mixing to non-photon final states are suppressed. Our explanation of this event, while being consistent with the terrestrial constraints, points to the non-standard cosmology.