Dark Side of the Neutron?

TL;DR

This paper explores the hypothesis that the discrepancy in neutron lifetime measurements indicates a dark decay channel involving a dark sector, supported by phenomenological models and experimental verification efforts.

Contribution

It proposes a novel interpretation of neutron lifetime discrepancy as evidence for neutron dark decay into a dark sector, with models and experimental strategies outlined.

Findings

Neutron dark decay channel with 1% branching fraction proposed

Phenomenological models involving a strongly self-interacting dark sector constructed

Experimental efforts to verify the dark decay hypothesis described

Abstract

We discuss our recently proposed interpretation of the discrepancy between the bottle and beam neutron lifetime experiments as a sign of a dark sector. The difference between the outcomes of the two types of measurements is explained by the existence of a neutron dark decay channel with a branching fraction 1%. Phenomenologically consistent particle physics models for the neutron dark decay can be constructed and they involve a strongly self-interacting dark sector. We elaborate on the theoretical developments around this idea and describe the efforts undertaken to verify it experimentally.