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The $g_{Vσγ}$-coupling constants in hadron electrodynamic

Michail P. Rekalo·Egle Tomasi-Gustafsson
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Abstract

Recent measurements of the branching ratios for the decays $ω\toπ^0π^0γ$ and $ρ^0\toπ^0π^0γ$ lead to coupling constants of the $Vσγ$-interaction ($V$ is a vector meson) one order of magnitude smaller than previously assumed to describe the threshold cross section of $γ+p\to p+ρ^0$ and the HERMES effect. The new $g^2_{Vσγ}$ couplings are in contradiction with the predictions of the QCD sum rules, but are in good agreement with VDM-estimation of the $σ\to γγ$-width.

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Michail P. Rekalo, Egle Tomasi-Gustafsson. 2003-01-28. The $g_{Vσγ}$-coupling constants in hadron electrodynamic. https://doi.org/10.1016/s0375-9474(03)01605-1

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