Journal article

Dirac-phase thermal leptogenesis in the extended type-I seesaw model

Matthew J Dolan, Tomasz P Dutka, Raymond R Volkas

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS | IOP PUBLISHING LTD | Published : 2018

Abstract

Motivated by the fact that δCP, the Dirac phase in the PMNS matrix, is the only CP-violating parameter in the leptonic sector that can be measured in neutrino oscillation experiments, we examine the possibility that it is the dominant source of CP violation for leptogenesis caused by the out-of-equilibrium decays of heavy singlet fermions. We do so within a low-scale extended type-I seesaw model, featuring two Standard Model singlet fermions per family, in which lepton number is approximately conserved such that the heavy singlet neutrinos are pseudo-Dirac. We find that this produces a predictive model of leptogenesis. Our results show that for low-scale thermal leptogenesis, a pure inverse-..

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Grants

Funding Acknowledgements

This work was supported in part by the Australian Research Council. TPD thanks Stephen J. Lonsdale and Thomas Hugle for helpful discussion along with Apostolos Pilaftsis and Avelino Vicente for valuable email correspondence.