The KM3NeT 220 PeV event: a neutrino messenger from the grand unification scale?

Vernon Barger

The KM3NeT 220 PeV event: a neutrino messenger from the grand unification scale?

High Energy Physics - Phenomenology 2026-07-12 v1 High Energy Astrophysical Phenomena

Authors: Vernon Barger

Abstract

The 220~PeV neutrino KM3-230213A, in tension with IceCube and Auger limits unless it is a narrow transient feature, admits a two-body reading: the decay $X \to \nu\bar\nu$ of a relic with $m_X = 4.4\times10^{8}$ ~GeV. The flux fixes $\tau/f$ , lifetime over dark-matter fraction, and the lifetime fixes an effective coupling $G_{\rm eff} \sim 10^{-46}$ ~GeV $^{-2}$ ; for a flavored onium decaying through one electroweak-Higgs insertion the mediator lands near $10^{16}$ ~GeV, so energy and rate together read out the grand-unified scale. We develop the construction and its tests against the astrophysical alternative.

Keywords

KM3NeT neutrino grand unified theory dark matter decay PeV

Cite

@article{arxiv.2607.10760,
  title  = {The KM3NeT 220 PeV event: a neutrino messenger from the grand unification scale?},
  author = {Vernon Barger},
  journal= {arXiv preprint arXiv:2607.10760},
  year   = {2026}
}