We report a measurement of the branching fraction ratios R(D ( * ) ) ofB → D ( * ) τ −ν τ relative tō B → D ( * ) −ν (where = e or µ) using the full Belle data sample of 772 × 10 6 BB pairs collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e + e − collider. The measured values are R(D) = 0.375 ± 0.064(stat.) ± 0.026(syst.) and R(D * ) = 0.293 ± 0.038(stat.) ± 0.015(syst.). The analysis uses hadronic reconstruction of the tag-side B meson and purely leptonic τ decays. The results are consistent with earlier measurements and do not show a significant deviation from the standard model prediction.

The cross section for ee+ e- → π+ π- J/ψ between 3.8 and 5.5 GeV is measured with a 967  fb(-1) data sample collected by the Belle detector at or near the Υ(nS) (n = 1,2,…,5) resonances. The Y(4260) state is observed, and its resonance parameters are determined. In addition, an excess of π+ π- J/ψ production around 4 GeV is observed. This feature can be described by a Breit-Wigner parametrization with properties that are consistent with the Y(4008) state that was previously reported by Belle. In a study of Y(4260) → π+ π- J/ψ decays, a structure is observed in the M(π(±)J/ψ) mass spectrum with 5.2σ significance, with mass M = (3894.5 ± 6.6 ± 4.5)  MeV/c2 and width Γ = (63 ± 24 ± 26)  MeV/c2, where the errors are statistical and systematic, respectively. This structure can be interpreted as a new charged charmoniumlike state.

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We report a measurement of the process γγ * → π 0 with a 759 fb −1 data sample recorded with the Belle detector at the KEKB asymmetric-energy e + e − collider. The pion transition form factor, F (Q 2 ), is measured for the kinematical region 4 GeVGeV 2 , where −Q 2 is the invariant mass squared of a virtual photon. The measured values of Q 2 |F (Q 2 )| agree well with the previous measurements below Q 2 ≃ 9 GeV 2 but do not exhibit the rapid growth in the higher Q 2 region seen in another recent measurement, which exceeds the asymptotic QCD expectation by as much as 50%.

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