arXiv subjects

J. Yelton

Publications and source records attributed to J. Yelton.

40 records · Page 3Linked 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

Absolute Branching Fraction Measurements for Exclusive $D_s$ Semileptonic Decays

We measure the absolute branching fractions of $\Ds$ semileptonic decays where the hadron in the final state is one of $ϕ$, $η$, $\etap$, $\Ks$, $\Kstar$, and $f_0$, using $2.8 \times 10^5$ $\epm \to \Ds\Dsstar$ decays collected in the CLEO-c detector at a center-of-mass energy close to 4170 MeV. We obtain ${\cal B}(\Dsp\to ϕe^+ ν_e) =(2.29\pm 0.37 \pm 0.11)$%, ${\cal B}(\Dsp\to ηe^+ ν_e) =(2.48 \pm 0.29 \pm 0.13)$%, ${\cal B}(\Dsp\to \etap e^+ ν_e) =(0.91 \pm 0.33 \pm 0.05)$%, where the first uncertainties are statistical and the second are systematic. We also obtain ${\cal B}(\Dsp\to K^0 e^+ ν_e) =(0.37\pm 0.10 \pm 0.02)$%, and ${\cal B}(\Dsp\to K^{\star 0} e^+ ν_e) =(0.18 \pm 0.07 \pm 0.01)$%, which are the first measurements of Cabibbo suppressed exclusive $\Ds$ semileptonic decays, and, ${\cal B}(\Dsp\to f_0 e^+ ν_e) \times {\cal B}(f_0 \to \pip\pim) =(0.13\pm 0.04 \pm 0.01)$%. This is the first direct evidence of a semileptonic decay including a scalar meson in the final state.

hep-ex↗