On the possibility to observe neutron dark decay in nuclei

TL;DR

This paper explores the potential to observe neutron dark decay within nuclei, focusing on specific candidates like $^{11}$Be, to address neutron lifetime measurement discrepancies and propose experimental detection methods.

Contribution

It analyzes nuclear candidates for neutron dark decay, especially $^{11}$Be, and discusses experimental approaches for detecting such decay modes.

Findings

$^{11}$Be is a promising candidate for observing neutron dark decay.

Neutron dark decay could occur in nuclei with low neutron binding energy.

Potential experimental signatures for neutron dark decay are identified.

Abstract

As proposed recently by Fornal and Grinstein, neutrons can undergo a dark matter decay mode which was not observed before. Such a decay could explain the existing discrepancy between two different methods of neutron lifetime measurements. If such neutron decay is possible, then it should occur also is nuclei with sufficiently low neutron binding energy. We examine a few nuclear candidates for the dark neutron decay and we consider possibilities of their experimental identification. In more detail we discuss the case of $^{11}$Be which appears as the most promising nucleus for the observation of the neutron dark decay.