相关论文: Charmonium from CLEO
This review briefly outlines recent experimental results from the charmonium system. These include new measurements of the M1 radiative transition rates $B(\psi(1S,2S)\to\gamma\eta_c(1S))$; new insights into the mass of the $\eta_c(1S)$;…
Charmonium systems in two-flavour QCD at non-zero temperature are studied at, and above the deconfining transition. Using anisotropic lattices the MEM approach is used to extract spectral functions for these channels. By carefully varying…
The charmonium spectrum is calculated with two nonrelativistic quark models, the linear potential model and the screened potential model. Using the obtained wavefunctions, we evaluate the electromagnetic transitions of charmonium states up…
Charmonium is a bound state of a charmed quark and a charmed antiquark, and a charmoniumlike state is a resonant structure that contains a charmed quark and antiquark pair but has properties that are incompatible with a conventional…
Using a sample of 2.59 times 10^7 psi(2S) decays collected by the CLEO--c detector, we present results of a study of chi_{c0} and chi_{c2} decays into two-meson final states. We present the world's most precise measurements of the…
Recent results from BES and CLEOc experiments on charmonium decays using J/psi, psi' and psi'' data samples collected in e+e- annihilation are reviewed, including the measurement of the relative phase between strong and electromagnetic…
We report first results for spectral functions of charmonium in 2-flavour QCD. The spectral functions are determined from vector and pseudoscalar correlators on a dynamical, anisotropic lattice. J/psi and eta_c are found to survive well…
In the light of SU(3) flavor symmetry, the effective interaction Hamiltonian in tensor form is obtained by virtue of group representation theory. The strong and electromagnetic breaking effects are treated as a spurion octet so that the…
This talk reviews recent experimental results on selected topics in the spectroscopy of charmonia, charmonium-like states and light mesons.
We investigate E1 radiative transitions within charmonium in a relativistic approach based on light-front QCD. In quantum field theory, two sets of processes are pure E1: $\chi_{c0} \to J/\psi \gamma$ ($\psi\to \chi_{c0}\gamma$) and $h_c…
We extend our original study in Ref. [1] on the production of $C=+$ charmonium states $X=\eta_c(1S/2S)$ and $\chi_{cJ}(1P/2P)$ in $e^+e^-\to\gamma~+~X$ at B factories to the BEPCII/BESIII energy region with $\sqrt{s}=4.0\mbox{-}5.0$ GeV. In…
Corrections of order $\alpha^4$Ry are calculated for the singlet states $1^1S_0$ and $2^1S_0$ of the helium atom. The result for $1^1S_0$ state is in slight disagreement with that of Korobov and Yelkhovsky in [Phys. Rev. Lett. {\bf 87},…
Using the CLEO-II detector at the CESR $e^+e^-$ storage ring running at the center-of-mass energy around 10.6 GeV, we have studied exclusive production of charmonium states in two-photon collisions. Employing a dataset comprising 3.0 ${\rm…
We present results for charmonium correlators and spectral functions in 2-flavour CD on anisotropic lattices. Our results indicate that the S-waves (J/psi and eta_c) survive up to temperatures close to 2T_c, while the P-waves (chi_c0 and…
We compute the O(alpha_s^2) correction to the decay rate eta_c --> gamma gamma and discuss its implications for precision quarkonium physics. We study the suitability of the ratio Gamma(J/psi --> e+e-)/Gamma(eta_c --> gamma gamma), in which…
We present a selection of recent results from the BESIII collaboration, including both charmonium and $D$ meson physics. We first discuss the observation of a charged, charmonium-like state, the $Z_c(3900)$. Conventional charmonium topics…
We outline a coherent strategy for exploring the four remaining narrow charmonium states [$\eta_{c}^{\prime}(2\slj{1}{1}{0})$, $h_{c}(1\slj{1}{2}{1})$, $\eta_{c2}(1\slj{1}{3}{2})$, and $\psi_{2}(1\slj{3}{3}{2})$] expected to lie below charm…
Charmonium spectroscopy gained renewed interest after the discovery in 2003 of the unpredicted X(3872) charmonium-like state, above the $D\overline{D}$ threshold. To date many charmonium-like states above the $D\overline{D}$ threshold have…
For charmonium's decaying to the final states involving merely light quarks, in light of SU(3) flavor symmetry, a systematic parametrization scheme is established, which involving binary decays, ternary decays and radiative decays.
Using a sample of 158 million \Upsilon(2S) events collected with the Belle detector, charmonium and charmonium-like states with even charge parity are searched for in \Upsilon(2S) radiative decays. No significant \chi_{cJ} or \eta_c signal…