Lifetime and decay of unstable particles in strong gravitational fields

TL;DR

This paper investigates how unstable particles decay in strong gravitational fields near black holes, revealing that relativistic effects and quasi-thermal spectra significantly influence decay processes.

Contribution

It introduces a semiclassical approach to analyze particle decay in circular orbits around compact objects, highlighting effects near the photon orbit.

Findings

Decay rates are affected by strong gravity and relativistic motion.

Quasi-thermal spectra influence particle decay similarly to Unruh radiation.

Significant effects occur near the photon orbit of black holes.

Abstract

We consider here the decay of unstable particles in geodesic circular motion around compact objects. For the neutron, in particular, strong and weak decay are calculated by means of a semiclassical approach. Noticeable effects are expected to occur as one approaches the photonic circular orbit of realistic black-holes. We argue that, in such a limit,the quasi-thermal spectrum inherent to extremely relativistic observers in circular motion plays a role similar to the Unruh radiation for uniformly accelerated observers.