Quarkonium-photoproduction prospects at a fixed-target experiment at the LHC (AFTER@LHC)

Abstract

We report on the potentialities offered by a fixed-target experiment at the LHC using the proton and ion LHC beams (AFTER@LHC project) regarding the study of J/psi exclusive-photoproduction in pA and AA collisions. The foreseen usage of polarised targets (hydrogen, deuteron, helium) gives access to measurements of the Single-Transverse-Spin Asymmetries of this exclusive process, therefore allowing one to access the helicity-flip Generalised Parton Distribution (GPD) Eg. We detail the expected yields of photoproduced J/psi in proton-hydrogen and lead-hydrogen collisions and discuss the statistical uncertainties on the asymmetry measurement for one year of data taking at the LHC.

Comments: proceeding of PHOTON 2017, Internation Conference on the Structure and the Interactions of the Photon, international workshop on Photon-Photon collisions, international workshop on high energy photon colliders