Flavour-Dependent Type II Leptogenesis

Abstract

We reanalyse leptogenesis via the out-of-equilibrium decay of the lightest right-handed neutrino in type II seesaw scenarios, taking into account flavour-dependent effects. In the type II seesaw mechanism, in addition to the type I seesaw contribution, an additional direct mass term for the light neutrinos is present. We consider type II seesaw scenarios where this additional contribution arises from the vacuum expectation value of a Higgs triplet, and furthermore an effective model-independent approach. We investigate bounds on the flavour-specific decay asymmetries, on the mass of the lightest right-handed neutrino and on the reheat temperature of the early universe, and compare them to the corresponding bounds in the type I seesaw framework. We show that while flavour-dependent thermal type II leptogenesis becomes more efficient for larger mass scale of the light neutrinos, and the bounds become relaxed, the type I seesaw scenario for leptogenesis becomes more constrained. We also argue that in general, flavour-dependent effects cannot be ignored when dealing with leptogenesis in type II seesaw models.

19 pages, 8 figures; v3: minor additions, typos corrected, results and conclusions unchanged

References in corpus (3)

• Quantum Boltzmann Equations and Leptogenesis
• Study of flavour dependencies in leptogenesis
• Thermal leptogenesis scenarios in the predictive left-right symmetric model

Cited by in corpus (5)

• Updated Values of Running Quark and Lepton Masses
• Deviations from Tri-bimaximal Neutrino Mixing in Type-II Seesaw and Leptogenesis
• Realistic Neutrinogenesis with Radiative Vertex Correction
• Neutrino Mixing and Leptogenesis in Type-II Seesaw Scenarios with Left-Right Symmetry
• The Minimal Type-II Seesaw Model and Flavor-dependent Leptogenesis