Test of electric charge conservation in dark matter direct detection experiment

TL;DR

This study used XENON-nT data to test electric charge conservation, setting a new, much stricter limit on possible violations, and demonstrating the potential of dark matter experiments for fundamental physics tests.

Contribution

The paper provides the first high-sensitivity search for electric charge nonconservation using dark matter detection data, significantly improving existing limits.

Findings

No evidence of charge nonconservation was found.

The limit on charge nonconservation lifetime was increased by two orders of magnitude.

Dark matter detectors can effectively test fundamental symmetries.

Abstract

Electric charge conservation (ECC) is typically taken as an axiom in the standard model. Searching for small violations with high-performance experiments could lead us to new physics. In this work, we tested ``invisible" electric charge nonconservation (ECNC) events with 1.16 ton$\cdot$year electron recoil data from the XENON-nT experiment. There was no statistically significant signal, and the ECNC limit was updated to $\tau(e^-\rightarrow{\nu_e+\bar{\nu}_e+\nu_e}) > 4.34 \times10^{27}$ yr. This work increases the limit by two orders of magnitude and shows that dark matter direct detection experiments have great potential for further ECC testing.