Upper Bound on the Energy of Particles and Their Secondary Neutrinos

TL;DR

This paper establishes an upper energy limit for particles accelerated in astrophysical shockwaves, which can be tested by neutrino experiments; exceeding this limit would suggest new physics beyond the Standard Model.

Contribution

It provides a universal upper bound on particle energies from shock acceleration, linking astrophysical observations to fundamental physics constraints.

Findings

Derived an energy upper limit for shock-accelerated particles.

Neutrino detection above this limit would challenge current physics models.

Discussed potential astrophysical sources of ultra-high energy cosmic rays.

Abstract

We derive an upper limit to the energy of nuclei accelerated via the Fermi mechanism in any relativistic shockwave, driven by any astrophysical engine. This bound is accessible to current and upcoming ultra-high energy neutrino experiments. Detection of a single neutrino with energy above the upper limit would exclude all sites of shock acceleration, and imply physics beyond the Standard Model. We comment on the possibility that relativistic flows launched by supermassive black hole mergers are the source of the observed ultra-high energy cosmic rays.