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Title: Search for charged lepton flavor violating decays of ϒ (1S)
A bstract We present a search for the charged lepton-flavor-violating decays ϒ(1 S ) → ℓ ± ℓ ′ ∓ and radiative charged lepton-flavour-violating decays ϒ(1 S ) → γ ℓ ± ℓ ′ ∓ [ ℓ , ℓ ′ = e, μ, τ ] using the 158 million ϒ(2 S ) sample collected by the Belle detector at the KEKB collider. This search uses ϒ(1 S ) mesons produced in ϒ(2 S ) → π + π − ϒ(1 S ) transitions. We do not find any significant signal, so we provide upper limits on the branching fractions at the 90% confidence level.
Authors:
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Award ID(s):
1913789
Publication Date:
NSF-PAR ID:
10345614
Journal Name:
Journal of High Energy Physics
Volume:
2022
Issue:
5
ISSN:
1029-8479
Sponsoring Org:
National Science Foundation
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