相关论文: On Radiative $\phi \to \eta \gamma$, $\phi \to \et…

The radiative transitions $\phi \to \eta \gamma$ and $\phi \to \eta^\prime \gamma$ are analysed using QCD sum-rules. The results we obtain for ${\cal B}(\phi \to \eta \gamma)=(1.15 \pm 0.2) 10^{-2}$ and ${\cal B}(\phi \to \eta^\prime…

With the recent investigations of $g^{\ast}g^{\ast}-\eta^{(\prime)}$ transition form factor and $\eta-\eta^{\prime}$ mixing scheme, we present an updated study of the radiative decays $J/\Psi\to\eta^{(\prime)}\gamma$ in perturbative QCD.…

The next-to-leading-order $O(1/Q^4)$ power correction for $\eta\gamma$ and $\eta^\prime\gamma$ form factors are evaluated and employed to explore the $\eta-\eta^\prime$ mixing. The parameters of the two mixing angle scheme are extracted…

A two mixing angle description of the pseudoscalar decay constants associated to the $\eta$-$\eta^\prime$ system is used to parametrize the theoretical amplitudes of the radiative decays $(\eta,\eta^\prime)\to\gamma\gamma$ and the coupling…

The radiative decays $\eta'(\eta)\rta\gamma\gamma$ are discussed. The modifications of the conventional PCAC formulae due to the gluonic contribution to the flavour singlet axial anomaly are given. The decay constants satisfy a modified…

We study the radiative decays $h_{c}\rightarrow\gamma\eta^{(\prime)}$ in the framework of perturbative QCD and evaluate analytically the one-loop integrals with the light quark masses kept. Interestingly, the branching ratios…

Using the $1.9 pb^{-1}$ of data collected with the CMD-2 detector at VEPP-2M the decay mode $\phi \to \eta \gamma$, $\eta \to \pi^+\pi^-\pi^0$ has been studied. The obtained branching ratio is B($\phi \to \eta \gamma) = (1.18 \pm 0.03 \pm…

We have measured the radiative decays phi -> eta gamma, phi ->etaprime gamma selecting pi+ pi- gamma gamma gamma final state in a sample of about 5 times 10^7 phi mesons produced at the Frascati phi factory DAFNE. We obtain Gamma(phi ->…

Rare radiative decay $\phi\to\eta\pi^0\gamma$ was studied with SND detector at {VEPP-2M} electron-positron collider and its branching ratio was measured: $B(\phi\to\eta\pi^0\gamma)=(0.88\pm0.14\pm0.09)\cdot 10^{-4}$. Significant…

Radiative decays \phi\to\eta\pi^0\gamma and \phi\to\pi^0\pi^0\gamma are studied assuming that these decays are caused through the intermediate a_0(980)\gamma and f_0(980)\gamma states, respectively. Fitting the experimental data of the…

We obtained two analytical constraints on the $\eta$-$\eta^\prime$ mixing parameters by considering two-photon decays of $\eta$ and $\eta^\prime$ [$\eta (\eta^\prime) \ra \gamma \gamma$], and productions of $\eta$ and $\eta^\prime$ in the…

In this article, we study the vertexes $\Omega_Q^*\Omega_Q \phi$ with the light-cone QCD sum rules, then assume the vector meson dominance of the intermediate $\phi(1020)$, and calculate the radiative decays $\Omega_Q^*\to \Omega_Q \gamma$.

Using a sample of $(225.3\pm 2.8)\times 10^{6}$ $J/\psi$ decays collected with the BESIII detector at BEPCII, searches for invisible decays of $\eta$ and $\eta^\prime$ in $J/\psi\to\phi\eta$ and $\phi\eta^\prime$ are performed. Decays of…

The $\eta$-$\eta^\prime$ pseudoscalar mixing angle and the gluonium content of the $\eta^\prime$ meson are deduced from an updated phenomenological analysis of $V\to P\gamma$ and $J/\psi\to VP$ decays. In absence of gluonium, the value of…

In this article, we calculate the $B_c^* \to B_c$ electromagnetic form-factor with the three-point QCD sum rules, then study the radiative decays $ B_c^{*\pm} \to B_c^{\pm} \gamma$. Experimentally, we can study the radiative transitions…

We calculate the decay rates for $\eta_c \to \gamma \gamma$, $J/\psi \to \gamma \eta_c$ and $J/\psi \to \eta_c e^+e^-$ in lattice QCD with $u$, $d$, $s$ and $c$ quarks in the sea for the first time. We improve significantly on previous…

An analysis of various radiative $VP\gamma$ decays is performed using the two mixing angle description of the $\eta$-$\eta^\prime$ system. The agreement is excellent. Our results are expressed both in the ``octet-singlet'' and in the…

We perform a thorough analysis of the VP\gamma(\gamma*) and P\gamma\gamma(\gamma*) decays in the resonance chiral theory, where V stand for the vector resonances \rho, K*, \omega, \phi, P stand for \pi, K, \eta, \eta' and \gamma*…

A value for the $\eta$-$\eta^\prime$ mixing angle is extracted from the data on $VP\gamma$ transitions using simple quark-model ideas. The set of data covers {\it all} possible radiative transitions between the pseudoscalar and vector meson…

The charmless nonleptonic $B\to \eta K$ decay is an useful probe to test the strong interaction dynamics part of the Standard Model. Within the QCD factorization framework, we analyse this particular decay by using the most recent data of…