Recent experimental results on charmonium $h_c(^1P_1)$, $η_c(1S)$ and $η_c(2S)$ from Belle, BaBar, CLEO and BESIII are reviewed. $h_c$ production and properties, the $η_c(1S)$ lineshape and the observation of $η_c(2S)$ in $ψ'$ decays are discussed.
Using CLEO-c data, we confirm the observation of D0 ->omega eta by BESIII. In the Dalitz Plot of D0 -> Kshort eta pi0, we find a background in the Kshort(->pipi)pi0 projection with a m(pipipi0) equal to the omega(782) mass. In a direct search for D0 -> (omega eta) we find a clear signal and measure BF(D0 ->omega eta) = (1.78+/-0.19+/-0.14) x 10**(-3), in good agreement with BESIII.
Using CLEO data, we report on the confirmation of the eta_b(1S0) ground state of bottomonium in the radiative decay Upsilon(3S) -> gamma eta_b. We determine its mass to be M(eta_b) = 9391.8 +- 6.6 +- 2.1 MeV, which corresponds to the hyperfine splitting Delta M_hf(1S) = 68.5 +- 6.6 +- 2.0 MeV, and the branching fraction B(Upsilon(3S) -> gamma eta_b) = (7.1 +- 1.8 +- 1.1) x 10^-4. These results agree with those previously reported by BaBar.
Observation of eta_c^{prime} Production in gamma gamma Fusion at CLEO
We report on the observation of the eta_{c} ^{prime}(2^{1} S_{0} ), the radial excitation of eta_{c} (1^{1} S_{0} ) ground state of charmonium, in the two-photon fusion reaction gamma gamma rightarrow eta_{c} ^{prime} rightarrow K_{S} ^{0}K^{pm}pi^{mp} in 13.6 fb^{-1} of CLEO II/II.V data and 13.1 fb^{-1} of CLEO III data. We obtain M( eta_{c} ^{prime})=3642.9 pm 3.1(stat) pm1.5(syst) MeV, and M( eta_{c} )=2981.8 pm1.3(stat) pm 1.5(syst) MeV. The corresponding values of hyperfine splittings between ^{1} S_{0} and ^{3} S_{1} states are Δ M_{hf} (1S)=115.1 pm 2.0 MeV, Delta M_{hf} (2S)=43.1 pm3.…
New measurements of the masses and decay branching fractions of charmonium and bottomonium states using the data collected by the CLEO detector are presented. These include CLEO identification of the singlet states eta_c'(2S), hc(1P), and eta_b(1S). Comparison with other experimental measurements and theoretical models is also presented.
Results of the latest CLEO contribution to bottomonium spectroscopy is presented, the confirmation of the eta_b(1S0) ground state of bottomonium in the radiative decay Upsilon(3S) -> gamma eta_b. The bottomonium hyperfine splitting is determined to be Delta M_hf(1S) = 68.5+-6.6+-2.0 MeV and the branching fraction B(Upsilon(3S) -> gamma eta_b=(7.1+-1.8+-1.1)x10^-4. These results are in good agreement with those reported by BaBar.
The latest results on chi_cJ(1P) decays from BESIII and CLEO-c are reviewed and compared to theoretical predictions. The experimental results use the final samples of chi_cJ(1P) decays from CLEO-c, obtained from 26 million psi(2S) decays, and the most recent samples from BESIII, from a starting sample of 106 million psi(2S) decays.
Using a 281 pb^-1 data sample collected at the psi(3770) resonance with the CLEO-c detector at the Cornell Electron Storage Ring, we report the first observation of D^+ to eta e^+ nu_e. We also set upper limits for D^+ to eta' e^+ nu_e and D^+ to phi e^+ nu_e that are about two orders of magnitude more restrictive than those obtained by previous experiments.
Using data acquired with the CLEO-c detector at the CESR e+e- collider, we measure branching fractions for J/psi, psi(2S), and psi(3770) decays to gamma pi0, gamma eta, and gamma eta'. Defining R_n = B[ psi(nS)-->gamma eta ]/B[ psi(nS)-->gamma eta' ], we obtain R_1 = (21.1 +- 0.9)% and, unexpectedly, an order of magnitude smaller limit, R_2 < 1.8% at 90% C.L. We also use J/psi-->gamma eta' events to determine branching fractions of improved precision for the five most copious eta' decay modes.
We present an effective field theory based extraction of the eta_c mass and width from a recent measurement by CLEO of the photon line shape in J/Psi -> eta_c gamma decay.
We review the recent results on D and Ds meson semileptonic decays from CLEO-c. Comparisons with lattice quantum chromodynamics (LQCD) calculations and implications for B physics are also discussed.
The CLEO-c Experiment has made several recent contributions to the study of charmonium decays. This review briefly outlines the CLEO-c analyses of charmonium that were completed or made public during 2010. Special attention is given to the discovery of the process e+e- to pi+pi-h_c at a center of mass energy of 4170 MeV.
In this talk, I review the recent experimental results on charmonium spectroscopy from BESIII, Belle, BaBar and CLEOc. Below the open-charm threshold, the masses and widths of spin-singlet states eta_c, eta_c(2S), h_c are measured with high precision. Above the threshold, chi_{c2}(2P) is identified in the process gamma gamma -> chi_{c2}(2P) -> gamma D bar{D}; Evidence of X(3823) is found in the M(chi_{c1} gamma) invariant-mass distribution for B -> gamma chi_{c1} K decays, the measured properties are consistent with the missing psi_2(1^{2}D_2) state.
We review the recent results on D and D_s meson semileptonic decays from CLEO-c, BABAR, and Belle. Comparisons with lattice quantum chromodynamics (LQCD) calculations and implications for B physics are also discussed.
We review recent experimental results on Bd and Bs mesons decays by the BaBar and Belle experiments. These include measurements of the color-suppressed decays B0bar to D(*)0h0, h0=pi0, eta, etaprime, omega, observation of the baryonic decay B0bar to Lambdac+ Lambdabar K-, measurements of the charmless decays B to eta h, h=K, pi, B to Kpi and observation of CP eigenstates in the Bs decays: B0s to J/psi f0(980), B0s to J/psi f0(1370) and B0s to J/psi eta. The theoretical implications of these results will be considered.
In this talk, I review the recent experimental developments on charmonium. These mainly include the precision measurements of spin-singlet states $\etac$, $\etac(2S)$, $h_c$, studies of the charmonium-like states X(3872) and the $Y$ states. Charmonium transitions and decays are also discussed.