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arXiv · 0809.2284

Search for Sub-threshold Photoproduction of J/Psi Mesons

P. Bosted·J. Dunne·C. A. Lee·P. Junnarkar·J. Arrington·R. Asaturyan·F. Benmokhtar·M. E. Christy·E. Chudakov·B. Clasie·S. H. Connell·M. M. Dalton·A. Daniel·D. Day·D. Dutta·R. Ent·N. Fomin·D. Gaskell·T. Horn·N. Kalantarians·C. E. Keppel·D. G. Meekins·H. Mkrtchyan·T. Navasardyan·J. Roche·V. M. Rodriguez·D. Kiselev·J. Seely·K. Slifer·M. Strikman·S. Tajima·G. Testa·Roman Trojer·F. R. Wesselmann·S. A. Wood·X. C. Zheng
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Abstract

A 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.

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P. Bosted, J. Dunne, C. A. Lee, P. Junnarkar, J. Arrington, R. Asaturyan, F. Benmokhtar, M. E. Christy, E. Chudakov, B. Clasie, S. H. Connell, M. M. Dalton, A. Daniel, D. Day, D. Dutta, R. Ent, N. Fomin, D. Gaskell, T. Horn, N. Kalantarians, C. E. Keppel, D. G. Meekins, H. Mkrtchyan, T. Navasardyan, J. Roche, V. M. Rodriguez, D. Kiselev, J. Seely, K. Slifer, M. Strikman, S. Tajima, G. Testa, Roman Trojer, F. R. Wesselmann, S. A. Wood, X. C. Zheng. 2008-11-14. Search for Sub-threshold Photoproduction of J/Psi Mesons. https://doi.org/10.1103/physrevc.79.015209

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