Vector Meson Dominance and Rho-Omega Mixing
نویسنده
چکیده
The scale of a phenomenologically successful charge-symmetry-violating nucleon-nucleon interaction, that attributed to meson exchange with a ∆I = 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 (∆I = 1) decay ω → ππ. The hadronic realization of this tadpole mechanism lies in the I = 1 a0 scalar meson. We show that measured hadronic and two-photon widths of the a0 meson, with the aid of the Vector Meson Dominance model, recover the universal Coleman-Glashow tadpole scale. PACS numbers: 14.40.cs, 12.70.+q, 13.75.cs, 21.30.+y [Keyword Abstract] charge symmetry breaking, rho-omega mixing, nucleon-nucleon potential, a0 scalar meson Electronic-mail address: [email protected] Electronic-mail address: [email protected] 1
منابع مشابه
Rho-omega Mixing and the Pion Electromagnetic Form-factor
The suggestion of momentum dependence in the amplitude for rho-omega mixing has generated concern over related implications for vector meson dominance and the photon-rho coupling. We discuss two established representations of vector meson dominance and show that one of these is completely consistent with such a coupling. We then apply it to a calculation of the pion electromagnetic form-factor....
متن کاملVector Meson Mixing and Charge Symmetry Violation [ Phys . Lett . B 370 ( 1996 ) 12 - 16 ]
We discuss the consistency of the traditional vector meson dominance (VMD) model for photons coupling to matter, with the vanishing of vector meson-meson and meson-photon mixing self-energies at q 2 = 0. This vanishing of vector mixing has been demonstrated in the context of rho-omega mixing for a large class of effective theories. As a further constraint on such models, we here apply them to a...
متن کاملMedium effects on the rho meson.
The property of a rho meson in dense nuclear matter is studied using the +CD sum rule. The spectral function appearing on the hadronic side of the sum rule is evaluated in the vector dominance model that takes into account the interaction between the rho meson and the pion. Including pion modification by the delta-hole polarization in the nuclear medium, we find that as the nuclear density incr...
متن کاملSeeing phi meson through the dilepton spectra in heavy-ion collisions
Dilepton spectra from the decay of phi mesons produced in heavy-ion collisions at SIS/GSI energies (∼ 2 GeV/nucleon) are studied in the relativistic transport model. We include phi mesons produced from baryon-baryon, pion-baryon, and kaon-antikaon collisions. The cross sections for the first two processes are obtained from an one-boson-exchange model, while that for the last process is taken to...
متن کاملRho meson in dense hadronic matter.
The spectral function of a rho meson that is at rest in dense hadronic matter and couples strongly to the pion is studied in the vector dominance model by including the effect of the delta hole polarization on the pion. With the free rho-meson mass in the Lagrangian, we find that both the rho-meson peak and width increase with increasing nuclear density, and that a low-mass peak appears at inva...
متن کامل