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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. 

A bstract 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, $$ \mathcal{B} $$ B ( τ ± → μ ± γ ) ≤ 4 . 2 × 10 − 8 and $$ \mathcal{B} $$ B ( τ ± → e ± γ ) ≤ 5 . 6 × 10 − 8 , are set at 90% confidence level. 

A bstract We present a measurement of the Cabibbo-Kobayashi-Maskawa unitarity triangle angle ϕ 3 (also known as γ ) using a model-independent Dalitz plot analysis of B + → D ( $$ {K}_S^0 $$ K S 0 h + h − ) h + , where D is either a D 0 or $$ \overline{D} $$ D ¯ 0 meson and h is either a π or K . This is the first measurement that simultaneously uses Belle and Belle II data, combining samples corresponding to integrated luminosities of 711 fb − 1 and 128 fb − 1 , respectively. All data were accumulated from energy-asymmetric e + e − collisions at a centre-of-mass energy corresponding to the mass of the Υ(4 S ) resonance. We measure ϕ 3 = (78 . 4 ± 11 . 4 ± 0 . 5 ± 1 . 0)°, where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is from the uncertainties on external measurements of the D -decay strong-phase parameters.