Dark Matter Induced Nucleon Decay Through the Neutron Portal

TL;DR

This paper explores how dark matter interactions via the neutron portal can cause nucleon decays, using Super-Kamiokande data to set constraints and discussing future experimental prospects.

Contribution

It reinterprets existing nucleon decay searches to constrain dark matter models involving the neutron portal and emphasizes the need for dedicated future analyses.

Findings

Lower bounds of about 1 TeV on the neutron portal operator scale for GeV-scale dark matter

Reinterpretation of Super-Kamiokande data constrains dark matter induced nucleon decays

Future Hyper-Kamiokande searches could improve sensitivity with dedicated analysis

Abstract

The neutron portal operator provides a theoretically motivated connection between the visible and dark sectors and features in several well-studied asymmetric dark matter models. This operator leads to dark matter induced nucleon decays that mimic the experimental signature of "ordinary" nucleon decays. In this work, we reinterpret Super-Kamiokande nucleon decay searches for $n \rightarrow \pi^0 \nu$ and $p \rightarrow \pi^+ \nu$ to constrain dark matter induced nucleon decays. For GeV-scale dark matter, we obtain lower bounds of $\mathcal{O}(1~\rm{TeV})$ on the scale of the effective neutron portal operator. We also discuss the prospects for future searches at Hyper-Kamiokande and highlight the importance of a dedicated experimental analysis with reduced systematic uncertainties.