Millicharged Particle Production in Pulsars via the Schwinger Effect

TL;DR

This paper investigates how millicharged particles can be produced in pulsars via the Schwinger effect, and how current dark matter detectors can constrain their properties based on pulsar emissions.

Contribution

It introduces a novel mechanism for millicharged particle production in pulsars and derives constraints from existing dark matter detection data.

Findings

Current XENONnT data constrains millicharged particles from the Crab pulsar to have charges below 10^{-6}.

Millicharged particles can be produced abundantly in pulsar environments via the Schwinger effect.

Detection prospects for millicharged particles in dark matter experiments are enhanced by pulsar emissions.

Abstract

Low mass particles with small electric charges can be produced abundantly in large electric fields via the Schwinger effect. We study the production rate of such particles inside the polar gap of nearby pulsars. After production they are accelerated above MeV energies by the local electric fields. These pulsar-produced millicharged particles can be detected at Earth in low-threshold dark matter direct detection experiments. We find that the current XENONnT data constrains millicharged particles produced in the Crab pulsar to have charges less than $O(10^{-6})$ for sub-eV masses.