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تسجيل مستخدم جديدDecays of eta and eta-prime within a chiral unitary approach
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Various decays of eta and eta-prime are investigated within the framework of U(3) chiral effective field theory in combination with a relativistic coupled-channels approach. Final state interactions are included by deriving s- and p-wave interaction kernels for meson-meson scattering from the chiral effective Lagrangian and iterating them in a Bethe-Salpeter equation. Very good agreement with experimental data is achieved.
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The decays eta, eta-prime --> pi+ pi- l+ l- (with l = e, mu) are investigated within a chiral unitary approach which combines the chiral effective Lagrangian with a coupled-channels Bethe-Salpeter equation. Predictions for the decay widths and spectra are given.
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Motivated by recent measurements of the radiative decay rates of the emph{P}-wave spin singlet charmonium $h_c$ to the light meson $eta$ or $eta^prime$ by the BESIII Collaboration, we investigate the decay rates of these channels at order $alpha alph
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