Spectator Effects during Leptogenesis in the Strong Washout Regime

Abstract

By including spectator fields into the Boltzmann equations for Leptogenesis, we show that partially equilibrated spectator interactions can have a significant impact on the freeze-out value of the asymmetry in the strong washout regime. The final asymmetry is typically increased, since partially equilibrated spectators "hide" a part of the asymmetry from washout. We study examples with leptonic and non-leptonic spectator processes, assuming thermal initial conditions, and find up to 50% enhanced asymmetries compared to the limit of fully equilibrated spectators. Together with a comprehensive overview of the equilibration temperatures for various Standard Model processes, the numerical results indicate the ranges when the limiting cases of either fully equilibrated or negligible spectator fields are applicable and when they are not. Our findings also indicate an increased sensitivity to initial conditions and finite density corrections even in the strong washout regime.

23 pages, 4 figures

References in corpus (4)

• Thermal production of relativistic Majorana neutrinos: Strong enhancement by multiple soft scattering
• The Sphaleron Rate through the Electroweak Cross-over
• Systematic approach to thermal leptogenesis
• Kubo relations and radiative corrections for lepton number washout

Cited by in corpus (14)

• Chiral effects in astrophysics and cosmology
• Dark Grand Unification in the Axiverse: Decaying Axion Dark Matter and Spontaneous Baryogenesis
• Natural Seesaw and Leptogenesis from Hybrid of High-Scale Type I and TeV-Scale Inverse
• Formation of Chiral Soliton Lattice
• Leptoflavorgenesis: baryon asymmetry of the Universe from lepton flavor violation
• Cosmic Evolution of Lepton Flavor Charges
• Complete leading-order standard model corrections to quantum leptogenesis
• Dirac leptogenesis from asymmetry wash-in via scatterings
• Conformal Leptogenesis in Composite Higgs Models
• A lower bound on the right-handed neutrino mass from wash-in leptogenesis
• Hot Leptogenesis
• The Neutrino Mass Bound from Leptogenesis Revisited
• Leptogenesis in the $\mu \tau$ basis
• Supersymmetric Baryogenesis in a Hybrid Inflation Model