Pair production of light pseudoscalar particles in strong inhomogeneous fields by the Schwinger mechanism

TL;DR

This paper calculates the rate at which light pseudoscalar particles, such as axions, are produced in strong, inhomogeneous electromagnetic fields via the Schwinger mechanism, impacting cosmic stability constraints.

Contribution

It provides a new calculation of pseudoscalar pair production rates in inhomogeneous fields, highlighting implications for axion physics and cosmic stability.

Findings

Axion stability requires Peccei-Quinn scale > 10^{10} GeV.

Pair production rates depend on field inhomogeneity and strength.

Constraints on axion models from astrophysical stability considerations.

Abstract

We calculate the rate for pair production of light pseudoscalars by strong inhomogeneous and static electric (magnetic) fields. We show that, in the case of axions, the stability of atoms over cosmic lifetimes is jeopardised unless the Peccei-Quinn symmetry breaking scale $f_a$ is larger than ${\cal O} (10^{10} GeV)$.