Related papers: Charmed quark component of the photon wave functio…
Using 11.6 1/pb of data collected in the energy range 0.864-1.06 GeV by CMD-2 at VEPP-2M, the rare decay mode phi to eta' gamma was observed via the decay chain eta' to pi+pi- eta, eta to pi+pi-pi0 or eta to pi+pi- gamma. The following…
We perform a lattice QCD calculation of the $\eta_c\to2\gamma$ decay width using a model-independent method that requires no momentum extrapolation of the off-shell form factors. This method also provides a straightforward and simple way to…
In this paper, we calculate the strong decays of $2^+$ heavy-light states, namely, the charmed $D^*_2(2460)^0$ meson and the charm-strange $D^*_{s2}(2573)^+$ meson. The method we adopt is the reduction formula, PCAC relation and low energy…
Exclusive and inclusive, semileptonic and non-leptonic, charmed decays of the B-meson are investigated in the context of a phenomenological quark model. Bound-state effects are taken care of by adopting a single (model-dependent)…
We suggest two methods (based on flavor SU(3) symmetry) to determine the CKM angle $\gamma$ using the decays $B_d$, $B^+ \to K \eta (\eta')$ and $B_s \to \pi \eta (\eta')$, respectively. Rescattering effects are partly included -- we…
A theoretical analysis of the partial inclusive B-->X_s gamma decay rate with a cut E_gamma>E_0 on photon energy must deal with short-distance contributions associated with three different mass scales: the hard scale m_b, an intermediate…
With accumulation of high statistics data at BES and CLEO-c, many new interesting channels can get enough statistics for partial wave analysis (PWA). Among them, $\psi \to \gamma p\bar p, \gamma\Lambda\bar \Lambda, \gamma\Sigma \bar\Sigma,…
We calculate the masses of $\chi_{\rm c}(3P)$ states with threshold corrections in a coupled-channel model. The model was recently applied to the description of the properties of $\chi_{\rm c}(2P)$ and $\chi_{\rm b}(3P)$ multiplets [Phys.\…
We calculate the electromagnetic (EM) decay widths of the $B^{\pm}_c(2S)$ meson, which is observed recently by the ATLAS Collaboration. The main EM decay channels of this particle are $1{^3S_1}\gamma$ and $1{P}\gamma$, which, in literature,…
We investigate a new method to probe the helicity of the photon emitted in the b -> s gamma transition. The method relies on the observation of interference effects between two resonance contributions, B -> K*(K gamma) gamma and B ->…
We extend our previous treatment of $\gamma^*p$ cross section based on Gribov's hypothesis to the case of photon-photon scattering. With the aid of two parameters, determined from experimental data, we separate the interactions into two…
We study the correction to the radiative $\pi^0$ decay width due to finite light quark mass. Using lattice QCD with the overlap fermion formulation, we calculate the three-point function of the form $<PV_\mu V_\nu>$ in the (Euclidean)…
We calculate the spectrum of $B_c$ mesons using a non-relativistic quark potential model. Using the calculated wave functions, we compute the radiative widths of $B_c$ excited states. The strong decay widths are calculated in a modified…
We compute charmonium spectral functions in 2-flavour QCD using the maximum entropy method and anisotropic lattices. We find that the S-waves (J/psi and eta_c) survive up to temperatures close to 2T_c, while the P-waves (chi_c0 and chi_c1)…
We have performed the first $n_f = 2+1+1$ lattice QCD computations of the properties (masses and decay constants) of ground-state charmonium mesons. Our calculation uses the HISQ action to generate quark-line connected two-point correlation…
In this work, we study the radiative decays of the $\Sigma_c$, $\Xi'_c$ and $\Omega_c$ charmed baryons, which belong to the flavor sextet ($\bf {6}_{\rm F}$), within the constituent quark model formalism. The electromagnetic transitions are…
We present a preliminary calculation of the charmonium spectrum using the dynamical 2+1 flavor $24^3\times 64$ domain wall fermion lattice configurations generated by the RBC and UKQCD collaborations. We use the relativistic heavy quark…
Two-photon and two-gluon annihilation rates of P-wave scalar charmonium and bottomonium up to third radial excited states are estimated in the relativistic Salpeter method. We solved the full Salpeter equation with a well defined…
We perform non-perturbative calculation of the \pi^0 to {\gamma}{\gamma} transition form factor and the associated decay width using lattice QCD. The amplitude for two-photon final state, which is not an eigenstate of QCD, is extracted…
We compute, for the first time using lattice QCD methods, radiative transition rates involving excited charmonium states, states of high spin and exotics. Utilizing a large basis of interpolating fields we are able to project out various…