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arXiv · hep-ex/0210036

Search for Lepton Flavor-Violating "tau -> mu gamma" decay

K. Inami·T. Hokuue·T. Ohshima·Belle collaboration
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Abstract

We search for the lepton flavor-violating "tau -> mu gamma" decay using 29.7 million tau pairs accumulated by the Belle experiment. The main background sources are found to be tau pairs with "tau -> mu nu nu" decay and radiative dimuon events. One event is observed in the signal region, while 2.5 +- 0.6 background events are expected. A preliminary upper limit Br(tau -> mu gamma) < 6 x 10^{-7} at the 90% confidence limit is obtained.

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K. Inami, T. Hokuue, T. Ohshima, Belle collaboration. 2002-10-15. Search for Lepton Flavor-Violating "tau -> mu gamma" decay. https://doi.org/10.1016/s0920-5632(03)80310-9

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