{mu}{tau} symmetry and radiatively generated leptogenesis
Abstract
We consider a {mu}{tau} symmetry in neutrino sectors realized at the GUT scale in the context of a seesaw model. In our scenario, the exact {mu}{tau} symmetry realized in the basis where the charged lepton and heavy Majorana neutrino mass matrices are diagonal leads to vanishing lepton asymmetries. We find that, in the minimal supersymmetric extension of the seesaw model with large tan{beta}, the renormalization group (RG) evolution from the GUT scale to seesaw scale can induce a successful leptogenesis even without introducing any symmetry breaking terms by hand, whereas such RG effects lead to tiny deviations of {theta}{sub 23} and {theta}{sub 13} from {pi}/4 and zero, respectively. It is shown that the right amount of the baryon asymmetry {eta}{sub B} can be achieved via socalled resonant leptogenesis, which can be realized at rather low seesaw scale with large tan{beta} in our scenario so that the wellknown gravitino problem is safely avoided.
 Authors:
 Department of Physics, Yonsei University, Seoul 120749 (Korea, Republic of)
 Center for Quantum Spacetime, Sogang University, Seoul 121742 (Korea, Republic of)
 Publication Date:
 OSTI Identifier:
 20933214
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevD.75.013012; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ASYMMETRY; BARYONS; MUON NEUTRINOS; SUPERSYMMETRY; SYMMETRY BREAKING; TAU NEUTRINOS
Citation Formats
Ahn, Y. H., Kim, C. S., Lee, Jake, and Kang, Sin Kyu. {mu}{tau} symmetry and radiatively generated leptogenesis. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.013012.
Ahn, Y. H., Kim, C. S., Lee, Jake, & Kang, Sin Kyu. {mu}{tau} symmetry and radiatively generated leptogenesis. United States. doi:10.1103/PHYSREVD.75.013012.
Ahn, Y. H., Kim, C. S., Lee, Jake, and Kang, Sin Kyu. Mon .
"{mu}{tau} symmetry and radiatively generated leptogenesis". United States.
doi:10.1103/PHYSREVD.75.013012.
@article{osti_20933214,
title = {{mu}{tau} symmetry and radiatively generated leptogenesis},
author = {Ahn, Y. H. and Kim, C. S. and Lee, Jake and Kang, Sin Kyu},
abstractNote = {We consider a {mu}{tau} symmetry in neutrino sectors realized at the GUT scale in the context of a seesaw model. In our scenario, the exact {mu}{tau} symmetry realized in the basis where the charged lepton and heavy Majorana neutrino mass matrices are diagonal leads to vanishing lepton asymmetries. We find that, in the minimal supersymmetric extension of the seesaw model with large tan{beta}, the renormalization group (RG) evolution from the GUT scale to seesaw scale can induce a successful leptogenesis even without introducing any symmetry breaking terms by hand, whereas such RG effects lead to tiny deviations of {theta}{sub 23} and {theta}{sub 13} from {pi}/4 and zero, respectively. It is shown that the right amount of the baryon asymmetry {eta}{sub B} can be achieved via socalled resonant leptogenesis, which can be realized at rather low seesaw scale with large tan{beta} in our scenario so that the wellknown gravitino problem is safely avoided.},
doi = {10.1103/PHYSREVD.75.013012},
journal = {Physical Review. D, Particles Fields},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

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