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Process eta -> pi^0 gamma gamma in the Nambu-Jona-Lasinio model

A. E. Radzhabov·M. K. Volkov
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Abstract

The decay width of the process eta -> pi^0 gamma gamma is calculated in the framework of the Nambu-Jona-Lasinio model. The momentum dependence of quark loops is taken into account. Three types of diagrams are considered: quark box, scalar(a0) and vector(rho, omega) pole diagrams. The obtained estimations are in satisfactory agreement with recent experimental data.

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A. E. Radzhabov, M. K. Volkov. 2006-10-13. Process eta -> pi^0 gamma gamma in the Nambu-Jona-Lasinio model. https://doi.org/10.1103/physrevd.74.113001

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