arXiv subjects

J. Y. Ge

Publications and source records attributed to J. Y. Ge.

23 records · Page 2Linked to original sources

arXiv2010

Branching fractions for chi_cJ -> p p-bar pi^0, p p-bar eta, and p p-bar omega

Using a sample of 25.9 million psi(2S) decays acquired with the CLEO-c detector at the CESR e^+e^- collider, we report branching fractions for the decays chi_cJ -> p p-bar pi^0, p p-bar eta, and p p-bar omega, with J=0,1,2. Our results for B(chi_cJ-> p p-bar pi^0) and B(chi_cJ-> p p-bar eta) are consistent with, but more precise than, previous measurements. Furthermore, we include the first measurement of B(chi_cJ-> p p-bar omega).

hep-ex↗

arXiv2010

Analysis of D+ to K- pi+ e+ nu_e and D+ to K- pi+ mu+ nu_mu Semileptonic Decays

Using a large sample (~11800 events) of D^+ into K^- pi^+ e^+ nu_e and D^+ into K^- pi^+ mu^+ nu_mu decays collected by the CLEO-c detector running at the psi(3770), we measure the helicity basis form factors free from the assumptions of spectroscopic pole dominance and provide new, accurate measurements of the absolute branching fractions for D^+ into K^- pi^+ e^+ nu_e and D^+ into K^- pi^+ mu^+ nu_mu decays. We find branching fractions which are consistent with previous world averages. Our measured helicity basis form factors are consistent with the spectroscopic pole dominance predictions for the three main helicity basis form factors describing D^+ into anti-K*0 ell^+ nu_mu decay. The ability to analyze D^+ into K^- pi^+ mu^+ nu_mu allows us to make the first non-parametric measurements of the mass-suppressed form factor. Our result is inconsistent with existing Lattice QCD calculations. Finally, we measure the form factor that controls non-resonant s-wave interference with the D^+ into anti-K*0 ell^+ nu_mu amplitude and search for evidence of possible additional non-resonant d-wave or f-wave interference with the anti-K*0.

hep-ex↗

arXiv2010

Measurement of the eta_b(1S) mass and the branching fraction for Upsilon(3S) --> gamma eta_b(1S)

We report evidence for the ground state of bottomonium, eta_b(1S), in the radiative decay Upsilon(3S) --> gamma eta_b in e^+e^- annihilation data taken with the CLEO III detector. Using 6 million Upsilon(3S) decays, and assuming Gamma(eta_b) = 10 MeV/c^2, we obtain B(Upsilon(3S) --> gamma eta_b) = (7.1 +- 1.8 +- 1.1) X 10^{-4}, where the first error is statistical and the second is systematic. The statistical significance is about 4 sigma. The mass is determined to be M(eta_b) = 9391.8 +- 6.6 +- 2.0 MeV/c^2, which corresponds to the hyperfine splitting Delta M_{hf}(1S)_b = 68.5 +- 6.6 +- 2.0 MeV/c^2. Using 9 million Upsilon(2S) decays, we place an upper limit on the corresponding Y(2S) decay, B(Y(2S) --> gamma eta_b) < 8.4 X 10^{-4} at 90 % confidence level.

hep-ex↗

arXiv2009

Study of D0 --> pi- e+ nu(e), D+ --> pi0 e+ nu(e), D0 --> K- e+ nu(e), and D+ --> anti-K0 e+ nu(e) in Tagged Decays of the psi(3770) Resonance

Using psi(3770) --> DDbar events collected with the CLEO-c detector at the Cornell e+ e- storage ring, tagged by fully reconstructing one D meson in a hadronic decay mode, we measure absolute branching fractions and differential decay rates for D0 --> pi- e+ nu(e), D+ --> pi0 e+ nu(e), D0 --> K- e+ nu(e), and D+ --> anti-K0 e+ nu(e). The measured decay rates are used to study semileptonic form factors governing these transitions and to test unquenched Lattice QCD (LQCD) calculations. We average our results with previously published CLEO-c measurements of the same quantities using a neutrino reconstruction technique. Combining LQCD calculations of form factor absolute normalizations f+(0) and measurements of f(pi)+(0)*|Vcd| and f(K)+(0)*|Vcs|, we find |Vcd| = 0.223(8)(3)(23) and |Vcs| = 1.019(10)(7)(106), where the uncertainties are statistical, experimental systematic, and from LQCD, respectively.

hep-ex↗

arXiv2009

Ds+ Exclusive Hadronic Decays Involving omega

Using data collected near the Ds*+ Ds- peak production energy Ecm=4170 MeV by the CLEO-c detector, we search for Ds+ exclusive hadronic decays involving omega. We find B(Ds+ -> pi+ omega) = (0.21 +- 0.09 +- 0.01)%, B(Ds+ -> pi+ pi0 omega) = (2.78 +- 0.65 +- 0.25)%, B(Ds+ -> pi+ pi+ pi- omega) = (1.58 +- 0.45 +- 0.09)%, B(Ds+ -> pi+ eta omega) = (0.85 +- 0.54 +- 0.06)%, B(Ds+ -> K+ omega) <0.24%, B(Ds+ -> K+ pi0 omega) <0.82%, B(Ds+ -> K+ pi+ pi- omega) <0.54%, and B(Ds+ -> K+ eta omega) <0.79%. The upper limits are at 90% confidence level.

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