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arXiv · hep-ph/0105278

Supersymmetric Model of Neutrino Mass and Leptogenesis with String-Scale Unification

Abstract

Adjoint supermultiplets (1,3,0) and (8,1,0) modify the evolution of gauge couplings. If the unification of gauge couplings occurs at the string scale, their masses are fixed at around $10^{13}$ GeV. This scale coincides with expected gaugino condensation scale in the hidden sector $M_{string}^{2/3} m^{1/3}_{3/2} \sim 10^{13}$ GeV. We show how neutrino masses arise in this unified model which naturally explain the present atmospheric and solar neutrino data. The out-of-equilibrium decay of the superfield (1,3,0) at $10^{13}$ GeV may also lead to a lepton asymmetry which then gets converted into the present observed baryon asymmetry of the Universe.

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Biswajoy Brahmachari, Ernest Ma, Utpal Sarkar. 2001-08-30. Supersymmetric Model of Neutrino Mass and Leptogenesis with String-Scale Unification. https://doi.org/10.1016/s0370-2693(01)01123-6

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