Dark Side of the Neutron?

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.

6 pages, 2 figures; Plenary talk presented at the International Workshop on Particle Physics at Neutron Sources 2018, Grenoble, France, May 24-26, 2018; based on: Phys. Rev. Lett. 120, 191801 (2018) [arXiv:1801.01124]; see also arXiv:1810.00862; to be published in EPJ Web of Conferences