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Title: Lepton flavor violation in a supersymmetric grand unified theory model with nonuniversal sfermion masses

Abstract

We analyze lepton flavor violating {tau}{yields}{mu}{gamma} and {mu}{yields}e{gamma} processes in a supersymmetric grand unified theory model in which sfermions have a special mass spectrum. It is assumed that only third generation sfermions which are contained in 10(Q,U{sup c},E{sup c}) of SU(5) can have a different mass from the others. This mass spectrum is derived from the E{sub 6} grand unified theory model with horizontal symmetries. It is shown that branching ratios of {tau}{yields}{mu}{gamma} and {mu}{yields}e{gamma} depend strongly on a right-handed stau mass. The weak scale stability requires a light stau, so large decay rates can be expected in this scenario. When the stau mass is around 150 GeV and tan{beta}{approx}10, the branching ratios can be larger than Br({tau}{yields}{mu}{gamma}){approx_equal}10{sup -8} and Br({mu}{yields}e{gamma}){approx_equal}5x10{sup -12}, which are within reach of future experiments. In addition, this model has an interesting feature that the final state charged lepton tends to have right-handed chirality.

Authors:
; ; ; ;  [1]
  1. Department of Physics, Nagoya University, Nagoya 464-8602 (Japan)
Publication Date:
OSTI Identifier:
20929570
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevD.75.115008; (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; BRANCHING RATIO; CHIRALITY; ELECTRONS; FLAVOR MODEL; GAMMA RADIATION; GEV RANGE 100-1000; GRAND UNIFIED THEORY; MASS SPECTRA; MUONS; PARTICLE DECAY; PARTICLE PRODUCTION; SUPERSYMMETRY; TAU PARTICLES

Citation Formats

Kim, S.-G., Maekawa, N., Matsuzaki, A., Sakurai, K., and Yoshikawa, T. Lepton flavor violation in a supersymmetric grand unified theory model with nonuniversal sfermion masses. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.115008.
Kim, S.-G., Maekawa, N., Matsuzaki, A., Sakurai, K., & Yoshikawa, T. Lepton flavor violation in a supersymmetric grand unified theory model with nonuniversal sfermion masses. United States. doi:10.1103/PHYSREVD.75.115008.
Kim, S.-G., Maekawa, N., Matsuzaki, A., Sakurai, K., and Yoshikawa, T. Fri . "Lepton flavor violation in a supersymmetric grand unified theory model with nonuniversal sfermion masses". United States. doi:10.1103/PHYSREVD.75.115008.
@article{osti_20929570,
title = {Lepton flavor violation in a supersymmetric grand unified theory model with nonuniversal sfermion masses},
author = {Kim, S.-G. and Maekawa, N. and Matsuzaki, A. and Sakurai, K. and Yoshikawa, T.},
abstractNote = {We analyze lepton flavor violating {tau}{yields}{mu}{gamma} and {mu}{yields}e{gamma} processes in a supersymmetric grand unified theory model in which sfermions have a special mass spectrum. It is assumed that only third generation sfermions which are contained in 10(Q,U{sup c},E{sup c}) of SU(5) can have a different mass from the others. This mass spectrum is derived from the E{sub 6} grand unified theory model with horizontal symmetries. It is shown that branching ratios of {tau}{yields}{mu}{gamma} and {mu}{yields}e{gamma} depend strongly on a right-handed stau mass. The weak scale stability requires a light stau, so large decay rates can be expected in this scenario. When the stau mass is around 150 GeV and tan{beta}{approx}10, the branching ratios can be larger than Br({tau}{yields}{mu}{gamma}){approx_equal}10{sup -8} and Br({mu}{yields}e{gamma}){approx_equal}5x10{sup -12}, which are within reach of future experiments. In addition, this model has an interesting feature that the final state charged lepton tends to have right-handed chirality.},
doi = {10.1103/PHYSREVD.75.115008},
journal = {Physical Review. D, Particles Fields},
number = 11,
volume = 75,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
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