Baryon asymmetry from leptogenesis with four zero neutrino Yukawa textures
Biswajit Adhikary; Ambar Ghosal; Probir Roy
Журнал:
Journal of Cosmology and Astroparticle Physics
Дата:
2011-01-01
Аннотация:
The generation of the right amount of baryon asymmetry η of the Universe from supersymmetric leptogenesis is studied within the type-I seesaw framework with three heavy singlet Majorana neutrinos N<sub>i</sub> (i = 1,2,3) and their superpartners. We assume the occurrence of four zeroes in the neutrino Yukawa coupling matrix Y<sub>ν</sub>, taken to be μτ symmetric, in the weak basis where N<sub>i</sub> (with real masses M<sub>i</sub> > 0) and the charged leptons l<sub>α</sub> (α = e,μ,τ) are mass diagonal. The quadrant of the single nontrivial phase, allowed in the corresponding light neutrino mass matrix m<sub>ν</sub>, gets fixed and additional constraints ensue from the requirement of matching η with its observed value. Special attention is paid to flavor effects in the washout of the lepton asymmetry. We also comment on the role of small departures from high scale μτ symmetry due to RG evolution.
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