Related papers: Charm annihilation effects on the hyperfine splitt…
In calculations of the hyperfine splitting in charmonium, the contributions of the disconnected diagrams is considered small and is typically ignored. We aim to estimate nonperturbatively the size of the resulting error, which could…
We study the properties of charmonium states at finite temperature in quenched lattice QCD on large and fine isotropic lattices. We perform a detailed analysis of charmonium correlation and spectral functions both below and above Tc. Our…
We present the first study of the charmonium spectrum using overlap fermions, on quenched configurations. Simulations are performed on $16^3 \times 72$ lattices, with Wilson gauge action at $\beta$ = 6.3345. We demonstrate that we have…
We present the results from a series of lattice simulations of the charmonium system using a highly-improved NRQCD action, both in the quenched approximation, and with n_f = 2 light dynamical quarks. The spectra show some evidence for…
Experimentally the charmonium hyperfine splitting is $M_{J/\psi}-M_{\eta_c}=117$ MeV and current lattice results are generally below this value. The difference could be due to the effects of the disconnected flavor singlet diagrams which…
The properties of charmonium states are or will be intensively studied by the B-factories Belle II and BESIII, the LHCb and PANDA experiments and at a future Super-c-tau Factory. Precise lattice calculations provide valuable input and…
We discuss the contribution of OZI-suppressed diagrams to the hyperfine splitting of charmonium in lattice QCD. We study valence quark mass regions from strange to charm quark masses. No contribution of the disconnected diagram is seen in…
We present results from a series of NRQCD simulations of the charmonium system, both in the quenched approximation and with n_f = 2 dynamical quarks. The spectra show evidence for quenching effects of ~10% in the S- and P-hyperfine…
We study charmonium using the standard relativistic formalism in the quenched approximation, on a set of lattices with isotropic lattice spacings ranging from 0.1 to 0.04 fm. We concentrate on the calculation of the hyperfine splitting…
We present our final results of the charmonium spectrum in quenched QCD on anisotropic lattices. Simulations are made with the plaquette gauge action and a tadpole improved clover quark action employing $\xi = a_s/a_t = 3$. We calculate the…
We study the properties of charmonium states at finite temperature in quenched QCD on large and fine isotropic lattices. We perform a detailed analysis of charmonium correlation and spectral functions both below and above $T_c$. Our…
We present preliminary results using overlap fermions for the charmonium spectrum, in particular for hyperfine splitting. Simulations are performed on $16^3 \times 72$ lattices, with Wilson gauge action at $\beta=6.3345$. Depending on how…
We extend the formalism based on perturbative QCD that was developed in our previous work, and compute the hyperfine splittings of the bottomonium spectrum as well as the fine and hyperfine splittings of the charmonium spectrum. All the…
We study the fine splitting in charmonium spectrum in quark model with the channel coupling effect, including $DD$, $DD^*$, $D^*D^*$ and $D_sD_s$, $D_sD_s^*$, $D_s^*D_s^*$ channels. The interaction for channel coupling is constructed from…
Lattice QCD results on the spectroscopy of charmonium(like) states and open charm mesons are reviewed. Near-threshold states X(3872) and D_{s0}^*(2317) were treated rigorously for the first time and the searches for Z_c^+(3900), X(4140) and…
We investigate the influence of dynamical charm quarks on observables that depend explicitly on the charm quark fields, like the pseudo-scalar and vector masses $m_{\eta_c}$ and $m_{J/\psi}$, the hyperfine splitting…
We present high-precision results from lattice QCD for the mass splittings of the low-lying charmonium states. For the valence charm quark, the calculation uses Wilson-clover quarks in the Fermilab interpretation. The gauge-field ensembles…
In this work, we study the charmonium spectrum within an unquenched quark model including coupled-channel effects. In couple-channel calculations, we include all of the opened charmed meson channels with the once-subtracted method,…
We report here our lattice simulation on the charmonium spectra in the quenched approximation. Because the full adjustment on the nonperturbative parameters such as $C_E$, $C_B$, $m_0a_s$ and $r_s$ needs many calculation time, we only…
Charmonium is an attractive system for the application of lattice QCD methods. While the sub-threshold spectrum has been considered in some detail in previous works, it is only very recently that excited and higher-spin states and further…