相关论文: Interference effects in the decay \phi\to \pi^{0}\…

Using a low background data sample of $9.7\times10^{5}$ $J\psi\rightarrow\gamma\eta^\prime$, $\eta^\prime\rightarrow\gamma\pi^+\pi^-$ events, which are 2 orders of magnitude larger than those from the previous experiments, recorded with the…

We illustrate the progress of covariant QCD phenomenology for the description of meson coupling constants and form factors. As examples, we discuss the $\rho\pi\pi$ and $\gamma \pi\rho$ interactions, the $\rho$ contribution to the pion…

The problem of $\rho$- and $\omega$- mesons contributions to the background for $\eta \to \pi^0 e^+e^-$ decay and to the asymmetries in the decays $\eta \to \pi^+\pi^-\pi^0$ and $\eta \to \pi^+\pi^-\gamma$ is considered.

The decay (B^0)bar -> pi^+ pi^- gamma has a bremsstrahlung component determined by the amplitude for (B^0)bar -> pi^+ pi^-, as well as a direct component determined by the penguin interaction V_tb V^*_td c_7 O_7. Interference of these…

The amplitudes of $K \rightarrow \pi \gamma^* \rightarrow \pi e^+e^-$ and $K \rightarrow \pi \pi \gamma$ decays have been calculated within chiral Lagrangian approach including higher-order derivative terms and meson loops. The…

We report observations of radiative B meson decays into the K+pi-gamma and K+pi-pi+gamma final states. In the B0 -> K+pi-gamma channel, we present evidence for decays via an intermediate tensor meson state with a branching fraction of B(B0…

The $\phi \to \omega \pi^0$ decay is studied using the method of phenomenological chiral Lagrangians. It is shown that the weak hadronic current between $\omega$-and $\pi^0$ -mesons is equal to zero and this decay channel proceeds only due…

Based on the effective invariant amplitudes of the transitions $J/\psi\to\gamma X(J^P)$ and $X(J^P)\to\phi\phi$, the spin dependence of the $J/\psi\to\gamma X(J^P)\to\gamma\phi\phi$ decay amplitude is obtained in the case of the…

We use QCD sum-rules to study the decays $\phi \to \eta \gamma$ and $\phi \to \eta^\prime \gamma$, obtaining ${\cal B}(\phi \to \eta \gamma)=(1.15 \pm 0.2) 10^{-2}$ and ${\cal B}(\phi \to \eta^\prime \gamma)=(1.18 \pm 0.4) 10^{-4}$, in very…

It is long known that interference effects play an important role in understanding the shape of the $\pi^+\pi^-$ spectrum of resonances near the threshold. In this manuscript we investigate the role of the $\rho-\omega$ interference in the…

We investigate the feasibility of studying in-medium properties of the $\omega$ meson in photoproduction experiments via the decay $\omega\rightarrow\pi^0\gamma$. We use the GiBUU transport model to compare different methods of obtaining…

The scalar and vector meson exchange contributions to the doubly radiative decays $\eta^{(\prime)}\to\pi^0\gamma\gamma$ and $\eta^\prime\to\eta\gamma\gamma$ are analysed within the Linear Sigma Model and Vector Meson Dominance frameworks,…

The value of the $N^*(1535)N\rho$ coupling constant $g_{N^*N\rho}$ derived from the $N^*(1535) \to N\rho \to N \pi \pi$ decay is compared with that deduced from the radiative decay $N^*(1535) \to N \gamma$ using the vector-meson-dominance…

We perform a dispersive analysis of the $\omega\pi$ electromagnetic transition form factor, using as input the discontinuity provided by unitarity below the $\omega\pi$ threshold and including for the first time experimental data on the…

The decay widths \phi \to \gamma f_0(980) and \phi \to \gamma a_0(980) are calculated taking into account the finite widths of the scalar resonances f_0(980) and a_0(980). The latter are shown to be essential in order to obtain meaningful…

We present the first and complete dispersion relation analysis of the inner radiative corrections to the axial coupling constant $g_A$ in the neutron $\beta$-decay. Using experimental inputs from the elastic form factors and the…

We present an analysis of the radiative decay $\phi \to \gamma \pi^0 \pi^0$ in a dispersive framework, where the two-pion subsystem undergoes strong final-state interactions that cover the $f_0(500)$ and $f_0(980)$ regions. We employ a…

We review the relationship between the pion decay constant $f_\pi$, the chiral symmetry restoration temperature $T_c$ and the phenomenology of low energy chiral symmetry breaking in view of the recent confirmation of the existence of a…

We present a calculation of the rare decay mode D^0 -> gamma gamma, in which the long distance contributions are expected to be dominant. Using the Heavy Quark Chiral Perturbation Theory Lagrangian with a strong g coupling as recently…

The radiative decays of the phi meson are known to be a good source of information about the a0(980) and f0(980) scalar mesons. We discuss these decays starting from a non-linear model Lagrangian which maintains the (broken) chiral symmetry…