Search for lepton-flavor-violating tau-lepton decays to l gamma at Belle

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2021-10-04, 2021-10-04
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Charged lepton flavor violation is forbidden in the Standard Model but possible in several new physics scenarios. In many of these models, the radiative decays τ± → ℓ±γ (ℓ = e, μ) are predicted to have a sizeable probability, making them particularly interesting channels to search at various experiments. An updated search via τ± → ℓ±γ using full data of the Belle experiment, corresponding to an integrated luminosity of 988 fb−1, is reported for charged lepton flavor violation. No significant excess over background predictions from the Standard Model is observed, and the upper limits on the branching fractions, B(τ± → μ±γ) ≤ 4.2 × 10−8 and B(τ± → e±γ) ≤ 5.6 × 10−8, are set at 90% confidence level. [Figure not available: see fulltext.].

Science & Technology, Physical Sciences, Physics, Particles & Fields, Physics, e(+)-e(-) Experiments, IDENTIFICATION, SIMULATION, ENERGY, 5106 Nuclear and Plasma Physics, 5107 Particle and High Energy Physics, 4902 Mathematical Physics, 49 Mathematical Sciences, 51 Physical Sciences