Asymmetries in Extended Dark Sectors: A Cogenesis Scenario

Abstract

The observed dark matter relic abundance may be explained by different mechanisms, such as thermal freeze-out/freeze-in, with one or more symmetric/asymmetric components. In this work we investigate the role played by asymmetries in determining the yield and nature of dark matter in scenarios with more than one dark matter particle. In particular, we show that the energy density of a particle may come from an asymmetry, even if the particle is asymptotically symmetric by nature. To illustrate the different effects of asymmetries we adopt a model with two dark matter components. We embed it in a cogenesis scenario that is also able to reproduce neutrino masses and the baryon asymmetry. The framework predicts a monochromatic neutrino line for some of the scenarios.

Leptogenesis, dark matter and gravitational waves from discrete symmetry breaking

“…Amongst recent theoretical efforts, of particular interest are those suggesting minimal extensions to the Standard Model (SM) to address the seemingly unrelated sectors of neutrinos, DM and excess of baryonic matter over anti-baryonic one in a unified framework [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. However, the requirement of tiny neutrino mass, a very specific DM relic density together with the fine-tuned matter-anti matter asymmetry leads naturally to heavy BSM physics or those weakly coupled to visible sector.…”