2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/220155A search was made for sub-threshold $J/ψ$ 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.19 pages, 7 figures, to be submitted to Phys. Rev. CNuclear ExperimentHigh Energy Physics - Experimenttext