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e^+ e^- Annihilation into J/psi + J/psi

Geoffrey T. Bodwin·Eric Braaten·Jungil Lee
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Abstract

Recent measurements by the Belle Collaboration of the exclusive production of two charmonia in e^+ e^- annihilation differ substantially from theoretical predictions. We suggest that a significant part of the discrepancy can be explained by the process e^+ e^- -> J/psi + J/psi. Because the J/psi + J/psi production process can proceed through fragmentation of two virtual photons into two cc-bar pairs, its cross section may be larger than that for J/psi +eta_c by about a factor 1.8, in spite of a suppression factor alpha^2/alpha_s^2 that is associated with the QED and QCD coupling constants.

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Geoffrey T. Bodwin, Eric Braaten, Jungil Lee. 2005-10-25. e^+ e^- Annihilation into J/psi + J/psi. https://doi.org/10.1103/physrevlett.90.162001

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