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arXiv · hep-ph/9308261

QCD calculation of J/psi+gamma mass distributions

E. L. Berger·K. Sridhar
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Abstract

We compute the J/psi+gamma invariant-mass distributions from the QCD subprocess g + g --> J/psi+gamma. At large masses, this subprocess is the dominant mechanism for J/psi+gamma production, and data could provide a good test of QCD. The mass distribution peaks at relatively small masses (3.4 - 4.0 GeV) and the subprocess could, therefore, represent a significant QCD background to J/psi+gamma decay of heavier charmonia. We also analyze the J/psi angular distribution in the J/psi+gamma rest frame.

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E. L. Berger, K. Sridhar. 1993-08-11. QCD calculation of J/psi+gamma mass distributions. https://doi.org/10.1016/0370-2693(93)91022-f

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