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Vector Meson Dominance and Rho-Omega Mixing

S. A. Coon·M. D. Scadron
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Abstract

The scale of a phenomenologically successful charge-symmetry-violating nucleon-nucleon interaction, that attributed to meson exchange with a $ΔI =1$ rho-omega transition, is set by the Coleman-Glashow SU(2) breaking tadpole mechanism. A single tadpole scale has been obtained from symmetry arguments, electromagnetic meson and baryon measured mass splittings, and the observed isospin violating ($ΔI=1$) decay $ω\to π^+π^-$. The hadronic realization of this tadpole mechanism lies in the $I = 1$ $a_0$ scalar meson. We show that measured hadronic and two-photon widths of the $a_0$ meson, with the aid of the Vector Meson Dominance model, recover the universal Coleman-Glashow tadpole scale.

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S. A. Coon, M. D. Scadron. 1998-08-06. Vector Meson Dominance and Rho-Omega Mixing. https://doi.org/10.1103/physrevc.58.2958

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