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Effective Chiral Theory for Radiative Decays of Mesons

E. Gedalin·A. Moalem·L. Razdolskaya
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Abstract

An extended $U(3)_L\bigotimes U(3)_R$ chiral theory which includes pseudoscalar and vector meson nonets as dynamic degrees of freedom is presented. We combine a hidden symmetry approach with a general procedure of including the $η'$ meson into chiral theory. The $U(3)_L\bigotimes U(3)_R$ and the SU(3) symmetries are broken by the mechanism based on quark mass matrix. Meson radiative decay widths are parameterized in terms of a single and real $η-η'$ mixing angle $θ_P$, a U(3)_V symmetry breaking scale parameter c_W, and the radiative decay constants $F_π, F_K, F_η, F_{η'}$, for the $π, η$, K, $η'$ mesons, respectively. Taking $F_π= 93 MeV$, a global fit to decay width data yields F_K/F_π= 1.16 \pm 0.11, F_η/F_π= 1.14\pm 0.04, F_{η'}/F_π= 1.09 \pm 0.04, c_W = -0.19 \pm0.03, θ_P =-(15.4 \pm 1.8)^o.

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E. Gedalin, A. Moalem, L. Razdolskaya. 2000-07-02. Effective Chiral Theory for Radiative Decays of Mesons. https://arxiv.org/abs/nucl-th/0006073

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