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Two photon decay of the pseudoscalars, the chiral symmetry breaking corrections

N. Nasrallah
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Abstract

The extrapolation of the decay amplitudes of the pseudoscalar mesons into two photons from the soft meson limit where it is obtained from the axial-anomaly to the mass shell involves the contribution of the 0^ - continuum. These chiral symmetry breaking corrections turn out to be large. The effects of these corrections on the calculated pi ^0 decay rate, on the values of the singlet-octet mixing angle and on the ratios f_8 / f_pi and f_0 / f_pi are discussed. The implications for the transition form factors gamma gamma* --> pseudoscalars are also evaluated and confronted with the available experimental data.

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N. Nasrallah. 2002-07-04. Two photon decay of the pseudoscalars, the chiral symmetry breaking corrections. https://doi.org/10.1103/physrevd.66.076012

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