Energy dependence of exclusive $J/\psi$ photoproduction off protons in
  ultra-peripheral p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV

Acharya, S.; Acosta, F. T.; Adam, J.; Adamová, D.; Adler, A.; Adolfsson, J.; Aggarwal, M. M.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahn, S. U.; Aiola, S.; Akindinov, A.; Al-Turany, M.; Alam, S. N.; Albuquerque, D. S.D.; Aleksandrov, D.; Alessandro, B.; Alfanda, H. M.; Ali, Y.; Alici, A.; Alkin, A.; Alme, J.; Bedda, C.; Caffarri, D.; Christakoglou, P.; der Kolk, N. van; Grelli, A.; Jaelani, S.; Keijdener, D. L.D.; Khabanova, Z.; Kuijer, P. G.; Lodato, D. F.; Margutti, J.; Mischke, A.; Mohanty, A. P.; Molina, R. Alfaro; Nooren, G.; Peitzmann, T.; Richert, T.; Rinella, G. Aglieri; Sas, M. H.P.; Simatovic, G.; Snellings, R. J.M.; Trzeciak, B. A.; van Doremalen, L. V.R.; van Leeuwen, M.; Veen, A. M.; Vermunt, L.; Yokoyama, H.

research

Energy dependence of exclusive $J/\psi$ photoproduction off protons in ultra-peripheral p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV

Abstract

The ALICE Collaboration has measured the energy dependence of exclusive photoproduction of

J/\psi

vector mesons off proton targets in ultra-peripheral p-Pb collisions at a centre-of-mass energy per nucleon pair

\sqrt{s_{\rm NN}} = 5.02

TeV. The e

^+

e

^-

and

\mu^+\mu^-

decay channels are used to measure the cross section as a function of the rapidity of the

J/\psi

in the range

-2.5 < y < 2.7

, corresponding to an energy in the

\gamma

p centre-of-mass in the interval

40 < W_{\gamma\mathrm{p}}<550

GeV. The measurements, which are consistent with a power law dependence of the exclusive

J/\psi

photoproduction cross section, are compared to previous results from HERA and the LHC and to several theoretical models. They are found to be compatible with previous measurements.Comment: 25 pages, 3 captioned figures, 3 tables, authors from page 19, published version, figures at http://alice-publications.web.cern.ch/node/455