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arXiv · 0804.3216

Two-photon decay of a light scalar quark-antiquark state

Francesco Giacosa
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Abstract

The two-photon decay of a light scalar quarkonium is evaluated in a local and a nonlocal approaches. It is shown that the two-photon decay, driven by a triangle quark-loop diagram, is smaller than 1 keV for a mass below 0.7 GeV.

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Francesco Giacosa. 2008-04-20. Two-photon decay of a light scalar quark-antiquark state. https://doi.org/10.1063/1.2973491

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