The $g_{V\sigma \gamma }$-coupling constants in hadron electrodynamic

Abstract

Recent measurements of the branching ratios for the decays $\omega \to {\pi }^0{\pi }^0\gamma$ and ${\rho }^0\to {\pi }^0{\pi }^0\gamma$ lead to coupling constants of the $V\sigma \gamma$-interaction ($V$ is a vector meson) one order of magnitude smaller than previously assumed to describe the threshold cross section of $\gamma +p\to p+{\rho }^0$ and the HERMES effect. The new $g_{V\sigma \gamma }^2$ couplings are in contradiction with the predictions of the QCD sum rules, but are in good agreement with VDM-estimation of the $\sigma \to \gamma \gamma$-width.

four figures, twelve pages

References in corpus (19)

• Experimental evidence for a light and broad scalar resonance in $D^{+}\to {\pi }^{-}{\pi }^{+}{\pi }^{+}$ decay
• Hadronic Structure in the Decay ${\tau }^{-}\to {\nu }_{\tau }{\pi }^{-}{\pi }^0{\pi }^0$ and the Sign of the Tau Neutrino Helicity
• Photoproduction of vector mesons off nucleons near threshold
• Radiative decay of rho^0 and phi mesons in a chiral unitary approach
• Photoproduction of Vector Mesons at Large Transfer
• Vector Meson Photoproduction with an Effective Lagrangian in the Quark Model
• Nuclear Effects on R = sigma_L / sigma_T in Deep-Inelastic Scattering
• Erratum to: "Nuclear Effects on R=σ_L/σ_T in Deep-Inelastic Scattering" Phys.Lett. B475(2000)386
• $\omega$ and $\rho$ Photoproduction with an Effective Quark Model Lagrangian
• Pion and photon couplings of N* resonances from scattering on the proton
• Experimental Study of rho -> pi0 pi0 gamma and omega -> pi0 pi0 gamma Decays
• Scalar sigma meson effects in rho and omega decays into pi0 pi0 gamma
• a_0(980) -> gamma gamma and f_0(980) -> gamma gamma: a consistent description
• The coupling constant g${}_{\rho \sigma \gamma }$ as derived from QCD sum rules
• The decay ${\rho }^0\to {\pi }^0{\pi }^0\gamma$ and the role of $\sigma$-meson
• Coherent Contributions of Nuclear Mesons to Electroproduction and the HERMES Effect
• The decay ${\rho }^0\to {\pi }^{+}+{\pi }^{-}+\gamma$ and the coupling constant g${}_{\rho \sigma \gamma }$
• g_{rho sigma gamma} coupling constant in light cone QCD
• Determination of the $g_{\rho \sigma \gamma }$ coupling constant through the process $\gamma +N\to N+V$ with circularly polarized photons

Cited by in corpus (3)

• Two photon decay of neutral scalars below 1.5 GeV in a chiral model for bar{q}q and bar{q}bar{q}qq states
• Higher meson resonances in $\rho \to {\pi }^0{\pi }^0\gamma$ and $\omega \to {\pi }^0{\pi }^0\gamma$
• Role of resonances in rho^0 -> pi^+ pi^- gamma