Timelike Compton Scattering at LHC

TL;DR

This paper explores the potential of timelike deeply virtual Compton scattering (TCS) in ultraperipheral collisions at the LHC to probe generalized parton distributions (GPDs) in the nucleon, highlighting a new experimental approach.

Contribution

It demonstrates that TCS dominates certain kinematic regions in ultraperipheral collisions, providing a novel method to study GPDs at small skewedness.

Findings

TCS mechanism dominates in specific kinematic regions.

Ultraperipheral collisions can effectively probe GPDs.

New experimental avenues for nucleon structure studies.

Abstract

Exclusive photoproduction of dileptons, gamma N ->l+l- N, is and will be measured in ultraperipheralcollisions at hadron colliders. We demonstrate that the timelike deeply virtual Compton scattering (TCS) mechanism gamma q -> l+l- q, where the lepton pair comes from the subprocess gamma q -> gamma* q, dominates in some accessible kinematical regions, thus opening a new way to study generalized parton distributions (GPD) in the nucleon at small skewedness.