2007/09/30 by Pei-Hong Gu, Hong-Jian He, Utpal Sarkar · 2 citations
Physics and Astronomy · #Neutrino Physics Research #Noncommutative and Quantum Gravity Theories #Particle physics theoretical and experimental studies #hep-ph
paper · pdf · doi:10.1016/j.physletb.2007.11.061
published as Phys.Lett.B659:634-639,2008 · 7 pages, 3 figures. Version accepted by PLB (minor rewording, refs added)
arxiv created 2007/11/14 · openalex publication_date 2007/12/04 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/02
We propose a new model for naturally realizing light Dirac neutrinos and explaining the baryon asymmetry of the universe through neutrinogenesis. To achieve these, we present a minimal construction which extends the Standard Model with a real singlet scalar, a heavy singlet Dirac fermion and a heavy doublet scalar besides three right-handed neutrinos, respecting lepton number conservation and a Z2 symmetry. The neutrinos acquire small Dirac masses due to the suppression of weak scale over a heavy mass scale. As a key feature of our construction, once the heavy Dirac fermion and doublet scalar go out of equilibrium, their decays induce the CP asymmetry from the interference of tree-level processes with the radiative vertex corrections (rather than the self-energy corrections). Although there is no lepton number violation, an equal and opposite amount of CP asymmetry is generated in the left-handed and the right-handed neutrinos. The left-handed lepton asymmetry would then be converted to the baryon asymmetry in the presence of the sphalerons, while the right-handed lepton asymmetry remains unaffected.