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arXiv · 0901.3917

\ga\ga and g g decay rates for equal mass heavy quarkonia

James T. Laverty·Stanley F. Radford·Wayne W. Repko
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Abstract

We present a calculation of the two-photon and two-gluon widths for the equal mass quarkonium states $^1S_0$, $^3P_0$ and $^3P_2$ of the charmonium and upsilon systems. The approach taken is based on using the full relativistic $q\bar{q}\to\ga\ga$ amplitude together with a wave function derived from the instantaneous Bethe-Salpeter equation. Momentum space radial wave functions obtained from an earlier fit of the charmonium and upsilon spectra are used to evaluate the necessary integrals.

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James T. Laverty, Stanley F. Radford, Wayne W. Repko. 2009-01-25. \ga\ga and g g decay rates for equal mass heavy quarkonia. https://arxiv.org/abs/0901.3917

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