摘要
We point out that two models that reconcile the neutron lifetime anomaly via dark decays of the neutron, also predict dark matter-neutron (χ¯ − n) annihilation that may be observable in neutron-antineutron oscillation and proton decay searches at Super-Kamiokande, Hyper-Kamiokande and DUNE. We study signatures of χ¯ n → γπ 0 (or multi-π 0 ) and χ¯ n → ϕγπ 0 (or ϕ+multi-π 0 ), where ϕ is an almost massless boson in one of the two models.