Related papers: Interference effects in the decay \phi\to \pi^{0}\…
We suggest that the $\gamma p \to \phi \eta p$ reaction cross section, in the kinematics where the $\eta p$ invariant mass in the final state lies between the threshold value (m$_p$+m$_\eta$) and the N*(1535) resonance mass, is largely…
Fermilab experiment E835 has observed proton-antiproton annihilation production of the charmonium state chi_c0 and its subsequent decay into pi^0 pi^0. Although the resonant amplitude is an order of magnitude smaller than that of the…
We revisit the coupled channel $K\bar{K}$ interactions and dynamically generate the resonances $f_0(980)$ and $a_0(980)$ within both the isospin and the physical bases. The $f_0(980)-a_0(980)$ mixing effects are generated in the scattering…
We employ QCD sum rules to calculate the coupling constant g$_{\rho\sigma\gamma}$ by studying the three point ${\rho\sigma\gamma}$-correlation function. Our results is consistent with the value of this coupling constant obtained using…
The branching ratio of the electromagnetic rare decays $\eta\to\pi^0\gamma\gamma$ and $\eta^\prime\to (\pi^0,\eta)\gamma\gamma$ are analysed in terms of scalar and vector meson exchange contributions using the frameworks of the Linear Sigma…
The contribution of interference effects to the radiation of a charged particle moving in a medium of randomly spaced plates is considered. In the angular dependent radiation intensity a peak appears at angles $\theta\sim\pi-\gamma^{-1}$,…
An experimental study of the $\eta'\to \pi^0\pi^0\eta \to 6\gamma$ decay has been conducted with the best up-to-date statistical accuracy, by measuring $\eta'$ mesons produced in the $\gamma p \to \eta' p$ reaction with the A2 tagged-photon…
Decays of the kind $B_s\to D_s^{\pm}K^\mp, D_s^{\ast\pm}K^\mp, ...$ and $B_d\to D^{\pm}\pi^\mp, D^{\ast\pm}\pi^\mp, ...$ allow us to probe $\phi_s+\gamma$ and $\phi_d+\gamma$, respectively, involving the angle $\gamma$ of the unitarity…
The decay $\eta'\rightarrow\pi^0\gamma\gamma$ is studied theoretically in the framework of the Vector Meson Dominance model (VMD). We find theoretically a significant contribution of the interference of $\omega-\rho$ and provide theoretical…
We search for the rare decay of the $D^{0}$ meson to two photons, $D^0 \rightarrow \gamma \gamma$, and present a measurement of the branching fraction for a $D^0$ meson decaying to two neutral pions, ${B}(D^0 \rightarrow \pi^0 \pi^0)$. The…
The short-distance contribution due to the $c\to u\gamma$ penguin as well as long-distance contributions are considered in an analysis of $D\to V\gamma$ decays, the latter being dominant. The matrix elements for nine $D\to V\gamma$…
We perform quantum-correlated measurements of the decay $D \to K^{0}_{\rm S}\pi^{+}\pi^{-}\pi^{0}$ using a data sample corresponding to an integrated luminosity of 0.82 fb$^{-1}$ collected at the $\psi(3770)$ resonance by the CLEO-c…
We have calculated the O(alpha) radiative corrections to the tau decay tau -> pi (K) nu, taking into account both the point meson contribution and the structure dependent radiation. We find for the ratio Gamma(tau -> pi nu (gamma)) /…
We investigate the $\omega\sigma\gamma$-vertex and estimate the coupling constant g$_{\omega\sigma\gamma}$ in the framework of the light cone QCD sum rules. We compare our result with the values of this coupling constant deduced from a…
We investigate the resonant contributions in the decays $\bar{B}^0_{(s)} \to D^0 \pi^{+}\pi^{-}$, $\bar{B}^0_{(s)} \to D^0 K^{+}K^{-}$, and $\bar{B}^{0} \rightarrow D^{0} \pi^{0}\eta$ by considering the final state interactions within the…
The decay mode $\psi(2S)\to J/\psi+\gamma\gamma$ is proposed in order to experimentally identify the effects of the coupling of charmonium states to the continuum $D\bar D$ states. To have a better understanding of such a two-photon decay…
Light meson ( $\pi,\ \sigma,\ a_0$) properties in the environment with chiral imbalance are analyzed with the help of meson effective Lagrangian associated with QCD. New spatial parity violating decays of scalar mesons arise as a result of…
We analyze the decays $\phi \to K\bar{K}$ utilizing a formulation of transition rates which explicitly exhibits corrections to Fermi's Golden Rule. These corrections arise in systems in which the phase space and/or matrix element varies…
Motivated by the discrepancies noted recently between the theoretical predictions of the electromagnetic $J/\psi \to \pi^0 \gamma^*$ transition form factor and the BESIII data, we reanalyze this transition form factor using the dispersive…
We study the reaction mechanism for the correlated $\pi^0\gamma$ emission in the photon induced reaction on the proton target. Since this reaction is studied in the GeV region, we assume that it proceeds through the formation of the vector…