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تسجيل مستخدم جديدSearch for Sub-threshold Photoproduction of J/Psi Mesons
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A search was made for sub-threshold $J/psi$ production from a carbon target using a mixed real and quasi-real Bremsstrahlung photon beam with an endpoint energy of 5.76 GeV. No events were observed, which is consistent with predictions assuming quasi-free production. The results place limits on exotic mechanisms that strongly enhance quasi-free production.
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