Quintessential Kination and Leptogenesis

Abstract

Thermal leptogenesis induced by the CP-violating decay of a right-handed neutrino (RHN) is discussed in the background of quintessential kination, i.e., in a cosmological model where the energy density of the early Universe is assumed to be dominated by the kinetic term of a quintessence field during some epoch of its evolution. This assumption may lead to very different observational consequences compared to the case of a standard cosmology where the energy density of the Universe is dominated by radiation. We show that, depending on the choice of the temperature T_r above which kination dominates over radiation, any situation between the strong and the super--weak wash--out regime are equally viable for leptogenesis, even with the RHN Yukawa coupling fixed to provide the observed atmospheric neutrino mass scale ~ 0.05 eV. For M< T_r < M/100, i.e., when kination stops to dominate at a time which is not much later than when leptogenesis takes place, the efficiency of the process, defined as the ratio between the produced lepton asymmetry and the amount of CP violation in the RHN decay, can be larger than in the standard scenario of radiation domination. This possibility is limited to the case when the neutrino mass scale is larger than about 0.01 eV. The super--weak wash--out regime is obtained for T_r << M/100, and includes the case when T_r is close to the nucleosynthesis temperature ~ 1 MeV. Irrespective of T_r, we always find a sufficient window above the electroweak temperature T ~ 100 GeV for the sphaleron transition to thermalize, so that the lepton asymmetry can always be converted to the observed baryon asymmetry.

13 pages, 8 figures

References in corpus (23)

• Cosmological Imprint of an Energy Component with General Equation of State
• Cosmological Tracking Solutions
• A lower bound on the right-handed neutrino mass from leptogenesis
• Resonant Leptogenesis
• Leptogenesis for Pedestrians
• Towards a complete theory of thermal leptogenesis in the SM and MSSM
• CP violating decays in leptogenesis scenarios
• CP Violation and Baryogenesis due to Heavy Majorana Neutrinos
• Effective dynamics of soft non-abelian gauge fields at finite temperature
• Quintessence and the Relic Density of Neutralinos
• The hot baryon violation rate is $O({\alpha }_W^5{T}^4)$
• Baryon Asymmetry, Neutrino Mixing and Supersymmetric SO(10) Unification
• SUSY Dark Matter and Quintessence
• Spectator processes and baryogenesis
• Radiatively induced leptogenesis in a minimal seesaw model
• Chern-Simons number diffusion with hard thermal loops
• Quintessential Enhancement of Dark Matter Abundance
• Quintessential Kination and Cold Dark Matter Abundance
• Degenerate minimal see-saw and leptogenesis
• Inflationary Cosmology Connecting Dark Energy and Dark Matter
• Connecting LHC, ILC, and Quintessence
• $\mu -\tau$ Symmetry and Radiatively Generated Leptogenesis
• Colliders as a simultaneous probe of supersymmetric dark matter and Terascale cosmology

Cited by in corpus (10)

• Axion cold dark matter in non-standard cosmologies
• Gravitational reheating in quintessential inflation
• Warm hilltop inflation
• Quintessential Kination and Thermal Production of Gravitinos and Axinos
• Enlarging mSUGRA parameter space by decreasing pre-BBN Hubble rate in Scalar-Tensor Cosmologies
• What is needed of a scalar field if it is to unify inflation and late time acceleration ?
• Gravity Waves as a Probe of Hubble Expansion Rate During An Electroweak Scale Phase Transition
• Tracking Quintessence and Cold Dark Matter Candidates
• Generation of neutrino dark matter, baryon asymmetry, and radiation after quintessential inflation
• Axions in Cold Dark Matter and Inflation Models