We present the new results of measurements of the exlusive cross sections of the e+ e− annihilation to charmed meson pairs as a function of √ ceneter-of-mass energy from the open charm threashold up to $ \sqrt s = {\rm{6 GeV}} $ using initial state radiation technique. The analysis is based on a data sample collected by the Belle detector with an integrated luminosity of 951 fb−1. The accuracy of the cross section measurement is increased by a factor of 2 in comparison with the first Belle study. We have performed the first angular analysis + −→ D*± D*∓ of the $ {e^{\rm{ + }}}{e^ - } \to {D^{* \pm }}{D^{* \mp }} $ process and decomposed this exclusive cross section into three components corresponding to the different D* helicities.
Extending a previous analysis1 the double charmonium production [Formula: see text] and [Formula: see text] has been investigated with a data set of 155 fb-1 with the Belle detector. Theoretical predictions for the cross section are one order of magnitude lower than the measured value and this discrepancy is still not understood. In a very recent update with a dataset of 285 fb-1 strong evidence for a new charmonium state at a mass of 3.940 GeV was found.
We report observations of the Cabibbo-suppressed decays B→ D(*)K and an upper limit for the decay branching fraction for [Formula: see text] using a 5.3fb-1 data sample accumulated at the ϒ(4S) resonance with the Belle detector at the KEKB e+e- asymmetric collider.
We present measurements of B → PV and VV decays based on 140 fb-1 of data recorded at the ϒ(4S) resonance with the Belle detector at the KEKB e+e- storage ring. Branching fractions of B → ηK*, ηρ+, ρπ0, and ρ+K* are measured; while upper limits of B → ηρ0 and ρ0K* decays are given. The polarization study of B → ϕK* is also updated.
We report recent results on the properties of the X(3872) produced via the B+→K+ X(3872) decay process in the Belle detector. We compare these properties with expectations for possible charmonium-state assignments.
Open charm studies at Belle