相关论文: Measurement of the Direct Photon Spectrum in $\Ups…
Using data taken with the CLEO III detector at the Cornell Electron Storage Ring, we have investigated the direct photon spectrum in the decays Upsilon(1S) -> gggamma, Upsilon(2S) -> gggamma, Upsilon}(3S) -> gggamma. The latter two of these…
The branching ratio and direct $CP$ asymmetry of the ${\Upsilon}(1S)$ ${\to}$ $B_{c}D_{s}$ weak decay are estimated with the perturbative QCD approach. It is found that (1) The direct $CP$-violating asymmetry is close to zero. (2) the…
Using 9.32, 5.88 million Upsilon(2S,3S) decays taken with the CLEO-III detector, we obtain five product branching fractions for the exclusive processes Upsilon(2S) => gamma chi_{b0,1,2}(1P) => gamma gamma Upsilon(1S) and Upsilon(3S) =>…
The ${\Upsilon}(1S)$ ${\to}$ $B_{c}D_{s}^{\ast}$ weak decay is studied with the perturbative QCD approach firstly. It is found that (1) main contributions to branching ratio come from the longitudinal and parallel helicity amplitudes, (2)…
We report on a study of exclusive radiative decays of the Upsilon(1S) resonance into a final state consisting of a photon and two K0s candidates. We find evidence for a signal for Upsilon(1S)->gamma f_2'(1525); f_2'(1525)->K0sK0s, at a rate…
We present an improved measurement of the $\eta'$ meson energy spectrum in $\Upsilon(1S)$ decays, using 1.2 fb^{-1} of data taken at the $\Upsilon(1S)$ center-of-mass energy with the CLEO III detector. We compare our results with models of…
We use 772$\times 10^6$ $B \bar{B}$ meson pairs collected at the $\Upsilon(4S)$ resonance with the Belle detector to measure the branching fraction for $\bar{B} \rightarrow X_s \gamma$. Our measurement uses a sum-of-exclusives approach in…
We report the observation of $\Upsilon(2S)\to\gamma\eta_{b}(1S)$ decay based on analysis of the inclusive photon spectrum of $24.7$ fb$^{-1}$ of $e^+ e^-$ collisions at the $\Upsilon(2S)$ center-of-mass energy collected with the Belle…
Using data taken with the CLEO-c detector at the Cornell Electron Storage Ring, we have investigated the direct photon momentum spectrum in the decay J/psi->gamma+gluon+gluon, via the 'tagged' process: e+e- -> psi(2S); psi(2S)->J/psi…
We report the first observation of the radiative decay of the $\Upsilon(1S)$ into a charmonium state. The statistical significance of the observed signal of $\Upsilon(1S) \to \gamma \chi_{c1}$ is 6.3 standard deviations including…
We report the measurement of the branching fraction of the $B^0 \to K_S^0 \pi^0 \gamma$ decay in $e^+ e^- \to \Upsilon(4S) \to B \overline{B}$ data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy collider and…
The feasibility of determining $\Delta \Gamma_s / Gamma_s$ from $B_s \to D_s^{(*)+} D_s^{(*)-}$ decay branching fraction measurements at $e^+ e^-$ colliders running on the $\Upsilon$(5S) resonance is discussed. The expected accuracies of…
Using a sample of 3.3 million Upsilon(4S) -> BBbar events collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR), we measure the branching fraction for B -> rho l nu, |V_ub|, and the partial rate (Delta Gamma) in…
Using a sample of 3.08 million psi(2S) decays collected at sqrt{s} = 3.686 GeV with the CLEO detector at the Cornell Electron Storage Ring, we have measured the branching fractions for psi(2S) decays to pseudoscalar pairs pi+pi-, K+K-, and…
We improve on a recent determination of alpha_s from Gamma(Upsilon(1S)-->X gamma)/Gamma(Upsilon(1S)-->X) with CLEO data by taking into account color octet contributions and avoiding any model dependence in the extraction. We obtain…
We present a calculation of the hindered M$1$ $\Upsilon(2S) \to \eta_b(1S) \gamma$ decay rate using lattice non-relativistic QCD. The calculation includes spin-dependent relativistic corrections to the NRQCD action through…
Using data taken with the CLEO III detector, 1.09 fb-1 at Upsilon(1S), and 1.28 fb-1 at Upsilon(2S), branching fractions have been measured for the first time for exclusive decays of each resonance into one hundred different final states…
In this study we present the first theoretical calculation of the form factor of the $\chi_{c0}(1P) \rar J/\psi \gamma $ and $\chi_{b0}(1P) \rightarrow \Upsilon(1S) \gamma $ decays in the frame work of QCD sum rules. We also find branching…
Using fully reconstructed $B_{s}$ mesons, we measure exclusive branching fractions for the decays $B_s \to D_s^{(*)+}D_s^{(*)-}$. The results are ${\cal B}(B^0_s\ra D^+_s D^-_s)=(0.58\,^{+0.11}_{-0.09}\,\pm 0.13)%$, ${\cal B}(B^0_s\ra…
We report on a study of exclusive radiative decays of the Upsilon(1S) resonance into the final states gamma pi^0 pi^0, gamma eta eta and gamma pi^0 eta, using 1.13 inverse femto-barn of e^+ e^- annihilation data collected at sqrt(s)= 9.46…