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Office of Scientific and Technical Information
 

Search for the lepton-flavor-violating τ− → e∓ℓ±ℓ− decays at Belle II

Journal Article · · Journal of High Energy Physics (Online)
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We present the result of a search for the charged-lepton-flavor violating decays τ− → e∓ℓ±ℓ−, where ℓ is a muon or an electron, using a data sample with an integrated luminosity of 428 fb−1 recorded by the Belle II experiment at the SuperKEKB e+e− collider. The selection of e+e− → τ+τ− events containing a signal candidate is based on an inclusive-tagging reconstruction and on a boosted decision tree to suppress background. Upper limits on the branching fractions between 1.3 and 2.5 × 10−8 are set at the 90% confidence level. These results are the most stringent bounds to date for four of the modes.
Research Organization:
Univ. of Hawaii, Honolulu, HI (United States)
Sponsoring Organization:
USDOE Office of Science (SC), High Energy Physics (HEP)
Grant/Contract Number:
AC06-76RL01830; SC0007983; SC0009824; SC0009973; SC0010007; SC0010073; SC0010118; SC0010504; SC0011784; SC0012704; SC0019230; SC0021274; SC0021616; SC0022350; SC0023470
OSTI ID:
3007251
Journal Information:
Journal of High Energy Physics (Online), Journal Name: Journal of High Energy Physics (Online) Journal Issue: 12 Vol. 2025; ISSN 1029-8479
Publisher:
Springer NatureCopyright Statement
Country of Publication:
United States
Language:
English

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Related Subjects

flavour physics
high energy physics
tau physics