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arXiv · 1010.1140

Effects of an extra U(1) axial condensate on the strong decays of pseudoscalar mesons

Enrico Meggiolaro
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Abstract

We consider a scenario (supported by some lattice results) in which a U(1)-breaking condensate survives across the chiral transition in QCD. This scenario has important consequences for the pseudoscalar-meson sector, which can be studied using an effective Lagrangian model. In particular, generalizing the results obtained in two previous papers, where the effects on the radiative decays eta,eta' --> gamma gamma were studied, in this paper we study the effects of the U(1) chiral condensate on the strong decays of the "light" pseudoscalar mesons, i.e., eta,eta' --> 3pi^0; eta,eta' --> pi^+ pi^- pi^0; eta' --> eta pi^0 pi^0; eta' --> eta pi^+ pi^-; and also on the strong decays of an exotic ("heavy") SU(3)-singlet pseudoscalar state eta_X, predicted by the model.

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Enrico Meggiolaro. 2014-02-20. Effects of an extra U(1) axial condensate on the strong decays of pseudoscalar mesons. https://doi.org/10.1103/physrevd.83.074007%2C%2010.1103%2Fphysrevd.89.039902

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