No abstract

We report the observation of two narrow structures in the mass spectra of the π(±)Υ(nS) (n=1, 2, 3) and π(±)h(b)(mP) (m=1, 2) pairs that are produced in association with a single charged pion in Υ(5S) decays. The measured masses and widths of the two structures averaged over the five final states are M(1)=(10,607.2±2.0)  MeV/c2, Γ(1)=(18.4±2.4)  MeV, and M(2)=(10,652.2±1.5)  MeV/c2, Γ(2)=(11.5±2.2)  MeV. The results are obtained with a 121.4  fb(-1) data sample collected with the Belle detector in the vicinity of the Υ(5S) resonance at the KEKB asymmetric-energy e+ e- collider.

With the full data sample of 772 × 10 6 BB pairs recorded by the Belle detector at the KEKB electronpositron collider, the decayB → D Ã τ −ν τ is studied with the hadronic τ decays τ − → π − ν τ and τ − → ρ − ν τ . The τ polarization P τ ðD Ã Þ in two-body hadronic τ decays is measured, as well as the ratio of the branching fractions

The cross section for e + e − → π + π − ψ(2S) between threshold and √ s = 5.5 GeV is measured using 673 fb −1 of data on and off the Υ(4S) resonance collected with the Belle detector at KEKB. Two resonant structures are observed in the π + π − ψ(2S) invariant mass distribution, one at 4361 ± 9 ± 9 MeV/c 2 with a width of 74 ± 15 ± 10 MeV/c 2 , and another at 4664 ± 11 ± 5 MeV/c 2 with a width of 48 ± 15 ± 3 MeV/c 2 , if the mass spectrum is parameterized with the coherent sum of two Breit-Wigner functions. These values do not match those of any of the known charmonium states.

We report measurement of the cross section of e þ e − → π þ π − ψð2SÞ between 4.0 and 5.