Constraining antibaryonic dark matter through correlated nucleon decay signatures

Abstract

Baryon number violation in the visible sector induced by antibaryonic dark matter provides a viable mechanism for low-scale baryogenesis. Two of the most sensitive probes of this scenario are neutron decay processes, such as n → ¯ν + invisible and n → π0 + invisible. In this work, we discuss the possible spontaneous breaking of baryon symmetry in the dark sector and the generation of di-nucleon decay processes, such as nn → ¯ν ¯ν and nn → π0π0 at one loop, arising from the operators responsible for induced nucleon decays. While the induced nucleon decay rates in this model depend on the dark matter density, dinucleon decay processes do not, providing a complementary probe of the new physics.We thus use nucleon and di-nucleon decay bounds to constrain the local density and mass of the antibaryonic dark matter.