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arXiv · hep-ph/9601206

Two-Photon Decays of Mesons in a Relativistic Quark Model

C. R. Munz
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Abstract

We present a relativistic calculation of two-photon decays for heavy and light mesons in the framework of the Salpeter equation for quark-antiquark states. The meson-photon-photon vertex is computed by reconstructing the Bethe-Salpeter vertex function and evaluating the four-dimensional Feynman diagram with off-shell quark amplitudes. The two-photon width for light and heavy quarkonia up to spin equal six are calculated with different parameter sets taken from the literature thus giving a complete overview on the mesonic two-photon physics. We find that relativistic effects including the negative energy components of the wave function are important for any two-photon width - even for heavy quarkonia - yielding a remarkable agreement with available data.

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C. R. Munz. 1996-01-03. Two-Photon Decays of Mesons in a Relativistic Quark Model. https://doi.org/10.1016/s0375-9474(96)00265-5

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