First Measurement of Near-Threshold J /ψ Exclusive Photoproduction off the Proton

A. Ali, M. Amaryan, E. G. Anassontzis, A. Austregesilo, M. Baalouch, F. Barbosa, J. Barlow, A. Barnes, E. Barriga, T. D. Beattie, V. V. Berdnikov, T. Black, W. Boeglin, M. Boer, W. J. Briscoe, T. Britton, W. K. Brooks, B. E. Cannon, N. Cao, E. ChudakovS. Cole, O. Cortes, V. Crede, M. M. Dalton, T. Daniels, A. Deur, S. Dobbs, A. Dolgolenko, R. Dotel, M. Dugger, R. Dzhygadlo, H. Egiyan, A. Ernst, P. Eugenio, C. Fanelli, S. Fegan, A. M. Foda, J. Foote, J. Frye, S. Furletov, L. Gan, A. Gasparian, V. Gauzshtein, N. Gevorgyan, C. Gleason, K. Goetzen, A. Goncalves, V. S. Goryachev, L. Guo, H. Hakobyan, A. Hamdi, S. Han, J. Hardin, G. M. Huber, A. Hurley, D. G. Ireland, M. M. Ito, N. S. Jarvis, R. T. Jones, V. Kakoyan, G. Kalicy, M. Kamel, C. Kourkoumelis, S. Kuleshov, I. Kuznetsov, I. Larin, D. Lawrence, D. I. Lersch, H. Li, W. Li, B. Liu, K. Livingston, G. J. Lolos, V. Lyubovitskij, D. Mack, H. Marukyan, V. Matveev, M. McCaughan, M. McCracken, W. McGinley, J. McIntyre, C. A. Meyer, R. Miskimen, R. E. Mitchell, F. Mokaya, F. Nerling, L. Ng, A. I. Ostrovidov, Z. Papandreou, M. Patsyuk, P. Pauli, R. Pedroni, L. Pentchev, K. J. Peters, W. Phelps, E. Pooser, N. Qin, J. Reinhold, B. G. Ritchie, L. Robison

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

© 2019 American Physical Society. We report on the measurement of the γp→J/ψp cross section from Eγ=11.8 GeV down to the threshold at 8.2 GeV using a tagged photon beam with the GlueX experiment. We find that the total cross section falls toward the threshold less steeply than expected from two-gluon exchange models. The differential cross section dσ/dt has an exponential slope of 1.67±0.39 GeV-2 at 10.7 GeV average energy. The LHCb pentaquark candidates Pc+ can be produced in the s channel of this reaction. We see no evidence for them and set model-dependent upper limits on their branching fractions B(Pc+→J/ψp) and cross sections σ(γp→Pc+)×B(Pc+→J/ψp).
Original languageEnglish
JournalPhysical Review Letters
DOIs
Publication statusPublished - 13 Aug 2019

Fingerprint Dive into the research topics of 'First Measurement of Near-Threshold J /ψ Exclusive Photoproduction off the Proton'. Together they form a unique fingerprint.

  • Cite this

    Ali, A., Amaryan, M., Anassontzis, E. G., Austregesilo, A., Baalouch, M., Barbosa, F., Barlow, J., Barnes, A., Barriga, E., Beattie, T. D., Berdnikov, V. V., Black, T., Boeglin, W., Boer, M., Briscoe, W. J., Britton, T., Brooks, W. K., Cannon, B. E., Cao, N., ... Robison, L. (2019). First Measurement of Near-Threshold J /ψ Exclusive Photoproduction off the Proton. Physical Review Letters. https://doi.org/10.1103/PhysRevLett.123.072001