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  1. ; ; ; ; ; ; ; ; ; ; et al (, Journal of High Energy Physics)
    A<sc>bstract</sc> We report a search for the charged-lepton flavor violation in Υ(2S) →ℓ∓τ±(ℓ=e, μ) decays using a 25 fb−1Υ(2S) sample collected by the Belle detector at the KEKBe+e−asymmetric-energy collider. We find no evidence for a signal and set upper limits on the branching fractions ($$ \mathcal{B} $$ B ) at 90% confidence level. We obtain the most stringent upper limits:$$ \mathcal{B} $$ B (Υ(2S)→ μ∓τ±)<0.23×10−6and$$ \mathcal{B} $$ B (Υ(2S)→ e∓τ±)<1.12×10−6. 
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  2. ; ; ; ; ; ; ; ; ; ; et al (, Physical Review D)
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  3. ; ; ; ; ; ; ; ; ; ; et al (, Physical Review D)
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  4. ; ; ; ; ; ; ; ; ; ; et al (, Physical Review Letters)
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  5. ; ; ; ; ; ; ; ; ; ; et al (, Physical Review D)
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  7. ; ; ; ; ; ; ; ; ; ; et al (, Journal of High Energy Physics)
    A<sc>bstract</sc> We measure the cross section ofe+e−→ηcJ/ψat the Υ(nS)(n= 1–5) on-resonance and 10.52 GeV off-resonance energy points using the full data sample collected by the Belle detector with an integrated luminosity of 955 fb−1. We also search for double charmonium production ine+e−→ηcJ/ψvia initial state radiation near theηcJ/ψthreshold. No evident signal of the double charmonium state is found, but evidence for thee+e−→ ηcJ/ψprocess is found with a statistical significance greater than 3.3σnear theηcJ/ψthreshold. The average cross section near the threshold is measured and upper limits of cross sections are set for other regions. 
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  8. ; ; ; ; ; ; ; ; ; ; et al (, Physical Review Letters)
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  9. ; ; ; ; ; ; ; ; ; ; et al (, Physical Review D)
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  10. ; ; ; ; ; ; ; ; ; ; et al (, Journal of High Energy Physics)
    A bstract Charged-lepton-flavor-violation is predicted in several new physics scenarios. We update the analysis of τ lepton decays into a light charged lepton ( ℓ = e ± or μ ± ) and a vector meson ( V 0 = ρ 0 , ϕ , ω , K *0 , or $$ \overline{K} $$ K ¯ *0 ) using 980 fb − 1 of data collected with the Belle detector at the KEKB collider. No significant excess of such signal events is observed, and thus 90% credibility level upper limits are set on the τ → ℓV 0 branching fractions in the range of (1.7–4 . 3) × 10 − 8 . These limits are improved by 30% on average from the previous results. 
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