http://arxiv.org/abs/2103.03650
The role of CP-violating decay and annihilation processes have been extensively studied in the context of generating cosmological particle-antiparticle asymmetries, both as sources of the asymmetry and its subsequent wash-out. In the scenarios for which the lowest order source of CP-violation is scattering processes, we highlight the role of additional CP-conserving annihilations in indirectly affecting the asymmetry generation. This stems from the strong dependence of the relevant out-of-equilibrium number densities on the rate of CP-conserving reactions. The net asymmetry generated, in turn, is proportional to the out-of-equilibrium number densities and the rate of CP-violation. Such CP-conserving scatterings occur naturally in scenarios of baryogenesis, leptogenesis and asymmetric dark matter production through scattering, as we illustrate through several examples. We find that the asymmetric yields for relevant particle-antiparticle systems can vary by orders of magnitude depending upon the relative size of the CP-conserving and violating reaction rates.
A. Ghosh, D. Ghosh and S. Mukhopadhyay
Mon, 8 Mar 21
23/65
Comments: 12 pages, 6 figures