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تسجيل مستخدم جديدAccount for axial vector mesons in the $etatopi^+pi^-gamma$ and $eta topi^+pi^-gamma$ decays
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The rates and spectra of the anomalous $etatopi^+pi^-gamma$ and $eta topi^+pi^-gamma$ decays are calculated. The approach is based on the effective meson Lagrangian obtained in the Nambu-Jona-Lasinio model with vector and axial-vector mesons by integrating out quark fields. The resulting action is affected by mixing between members of pseudoscalar $J^{PC}=0^{-+}$ and axial-vector $1^{++}$ nonets that violates some low-energy theorems. In this note we point out that a gauge covariant procedure to diagonalize this mixing allows for consistent description of the $etatopi^+pi^-gamma$ and $eta topi^+pi^-gamma$ decays.
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We investigate the rare radiative eta decay modes eta -> pi+ pi- gamma gamma and eta -> pi0 pi0 gamma gamma within the framework of chiral lagrangians at o(p^4) and present photon spectra for both processes.
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