Large t diffractive J/\psi photoproduction with proton dissociation in ultraperipheral pA collisions at LHC

TL;DR

This paper proposes using ultraperipheral pA collisions at the LHC to study large t elastic hard QCD Pomeron interactions via $J/\psi$ photoproduction with proton dissociation, extending energy reach beyond HERA.

Contribution

It introduces a novel experimental approach to probe Pomeron dynamics at higher energies using $J/\psi$ photoproduction in ultraperipheral collisions at the LHC.

Findings

Cross section varies by a factor of at least 20 over the energy range.

Energy dependence of elastic scattering can be studied over $10^3$ to $10^6$ GeV$^2$.

Feasible counting rates predicted for LHC detectors.

Abstract

We evaluate the large momentum transfer $J/\psi$ photoproduction with rapidity gaps in ultraperipheral proton-ion collisions at the LHC which provides an effective method of probing dynamics of large t elastic hard QCD Pomeron interactions. It is shown that the experimental studies of this process would allow to investigate the energy dependence of cross section of elastic scattering of a small $c\bar c$ dipole off the gluon over a wide range of invariant energies 10^3 < s_{c\bar c - gluon} < 10^6 GeV^2. The accessible energy range exceeds the one reached in \gamma p at HERA by a factor of 10 and allows the kinematic cuts which improve greatly sensitivity to the Pomeron dynamics as compared to the HERA measurements. The cross section is expected to change by a factor \ge 20 throughout this interval and our estimates predict quite reasonable counting rates for this process with the several of the LHC detectors.