Using 586pb^-1 of e^+e^- collision data at E_CM = 4170MeV, produced at the CESR collider and collected with the CLEO-c detector, we observe the process e^+e^- --> pi^+ pi^- h_c(1P). We measure its ...cross section to be 15.6+-2.3+-1.9+-3.0pb, where the third error is due to the external uncertainty on the branching fraction of psi(2S) --> pi^0 h_c(1P), which we use for normalization. We also find evidence for e^+e^- --> eta h_c(1P) at 4170MeV at the 3sigma level, and see hints of a rise in the e^+e^- --> pi^+ pi^- h_c(1P) cross section at 4260MeV.
We present the results of a Dalitz plot analysis of D^0 to K^0_S pi^0 pi^0 using the CLEO-c data set of 818 inverse pico-barns of e^+ e^- collisions accumulated at sqrt{s} = 3.77 GeV. This ...corresponds to three million D^0 D^0-bar pairs from which we select 1,259 tagged candidates with a background of 7.5 +- 0.9 percent. Several models have been explored, all of which include the K^*(892), K^*_2(1430), K^*(1680), the f_0(980), and the sigma(500). We find that the combined pi^0 pi^0 S-wave contribution to our preferred fit is (28.9 +- 6.3 +- 3.1)% of the total decay rate while D^0 to K^*(892)^0 pi^0 contributes (65.6 +- 5.3 +- 2.5)%. Using three tag modes and correcting for quantum correlations we measure the D^0 to K^0_S pi^0 pi^0 branching fraction to be (1.059 +- 0.038 +- 0.061)%.
We report the first observation of the decay D^+ -> eta' e^+ nu_e in two analyses, which combined provide a branching fraction of B(D+ -> eta' e nu) = (2.16 +/- 0.53 +/- 0.07) x 10^{-4}. We also ...provide an improved measurement of B(D+ -> eta e nu) = (11.4 +/- 0.9 +/- 0.4) x 10^{-4}, provide the first form factor measurement, and set the improved upper limit B(D+ -> phi e nu) < 0.9 x 10^{-4} (90% C.L.).
Phys.Rev.D84:012005,2011 We present the first search for the decay $D^+_{s}\to \omega e^{+}\nu$ to
test the four-quark content of the $D^+_{s}$ and the $\omega$-$\phi$ mixing
model for this decay. We ...use 586 $\mathrm{pb}^{-1}$ of $e^{+}e^{-}$ collision
data collected at a center-of-mass energy of 4170 MeV. We find no evidence of a
signal, and set an upper limit on the branching fraction of
$\mathcal{B}(D^+_{s}\to\omega e^+\nu)<$0.20% at the 90% confidence level.
Using 586 $\textrm{pb}^{-1}$ of $e^{+}e^{-}$ collision data acquired at
$\sqrt{s}=4.170$ GeV with the CLEO-c detector at the Cornell Electron Storage
Ring, we report the first observation of ...$D_{s}^{*+} \to D_{s}^{+} e^{+} e^{-}$
with a significance of $5.3 \sigma$. The ratio of branching fractions
$\calB(D_{s}^{*+} \to D_{s}^{+} e^{+} e^{-}) / \calB(D_{s}^{*+} \to D_{s}^{+}
\gamma)$ is measured to be $ 0.72^{+0.15}_{-0.13} (\textrm{stat}) \pm 0.10
(\textrm{syst})%$, which is consistent with theoretical expectations.
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 (4.0+/-1.3+/-0.6)x10^{-5}, consistent with previous observations of Upsilon(1S)->gamma f_2'(1525); f_2'(1525)->K+K-, and isospin. Combining this branching fraction with existing branching fraction measurements of Upsilon(1S)->gamma f_2'(1525) and J/psi->gamma f_2'(1525), we obtain the ratio of branching fractions: B(Upsilon(1S)->gamma f_2'(1525))/B(J/psi->gamma f_2'(1525))=0.09+/-0.02, approximately consistent with expectations based on soft collinear effective theory.
Phys.Rev.D83:054003,2011 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) => gamma chi_{b1,2}(1P) => gamma gamma Upsilon(1S). We observe the
transition chi_{b0}(1P) => gamma Upsilon(1S) for the first time. Using the
known branching fractions for BUpsilon(2S) => gamma chi_{bJ}(1P), we extract
values for Bchi_{bJ}(1P) => gamma Upsilon(1S) for J=0, 1, 2. In turn, these
values can be used to unfold the Upsilon(3S) product branching fractions to
obtain values for BUpsilon(3S) => gamma chi_{b1,2}(1P) for the first time
individually. Comparison of these with each other and with the branching
fraction BUpsilon(3S) => gamma chi_{b0} previously measured by CLEO provides
tests of relativistic corrections to electric dipole matrix elements.
We have searched for flavor-changing neutral current decays and lepton-number-violating decays of D^+ and D^+_s mesons to final states of the form h^+- e^-+ e^+, where h is either \pi or K. We use ...the complete samples of CLEO-c open-charm data, corresponding to integrated luminosities of 818 pb^-1 at the center-of-mass energy E_CM = 3.774 GeV containing 2.4 x 10^6 D^+D^- pairs and 602 pb^-1 at E_CM = 4.170 GeV containing 0.6 x 10^6 D^*+-_s D^-+_s pairs. No signal is observed in any channel, and we obtain 90% confidence level upper limits on branching fractions B(D^+ --> \pi^+ e^+ e^-) < 5.9 x 10^-6, B(D^+ --> \pi^- e^+ e^+) < 1.1 x 10^-6, B(D^+ --> K^+ e^+ e^-) < 3.0 x 10^-6, B(D^+ --> K^- e^+ e^+) < 3.5 x 10^-6, B(D^+_s --> \pi^+ e^+ e^-) < 2.2 x 10^-5, B(D^+_s --> \pi^- e^+ e^+) < 1.8 x 10^-5, B(D^+_s --> K^+ e^+ e^-) < 5.2 x 10^-5, and B(D^+_s --> K^- e^+ e^+) < 1.7 x 10^-5.
PDF