Timelike Compton scattering in ultraperipheral $pPb$ collisions

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.