Timelike Compton scattering in ultraperipheral $pPb$ collisions

TL;DR

This paper investigates timelike Compton scattering in ultraperipheral pPb collisions at the LHC to probe generalized parton distributions, estimating cross sections and interference effects within the detector's kinematic range.

Contribution

It provides the first detailed estimates of TCS, Bethe-Heitler, and interference contributions in ultraperipheral pPb collisions at the LHC, based on a specific GPD model.

Findings

Predicted TCS cross sections within LHC detector range.

Estimated interference effects between TCS and Bethe-Heitler processes.

Provided differential cross section calculations for experimental comparison.

Abstract

The study of exclusive processes in photon - induced interactions allow us to probe the generalized parton distributions (GPDs), which provide information about the 3 dimensional description of the quark and gluon content of hadrons. In this paper we investigate the timelike Compton scattering (TCS) in ultraperipheral $pPb$ collisions at the LHC. Such process is characterized by the exclusive dilepton production through the subprocess $\gamma p \rightarrow \gamma^*p \rightarrow l^+ l^- p$, with the real photon in the initial state being emitted by the nucleus. Assuming a given model for the GPDs, the TCS differential cross section is estimated as well the contribution associated to the interference between the TCS and Bethe - Heitler (BH) amplitudes. Predictions for the TCS, BH and interference contributions are presented considering the kinematical range covered by the LHC detectors.