# Exclusive production of a large mass photon pair

## TL;DR

This paper analyzes the photoproduction of high-mass photon pairs, revealing a unique amplitude structure and demonstrating its measurability at JLab with significant angular asymmetries.

## Contribution

It introduces a novel analysis of diphoton production involving valence quark distributions at specific kinematic points, with implications for experimental measurements.

## Key findings

- Amplitude proportional to valence quark GPDs at x=±ξ
- Process measurable at JLab energies
- Large angular asymmetry with linearly polarized photons

## Abstract

The scattering amplitude for photoproduction of a large invariant mass diphoton in the generalized Bjorken regime has a very peculiar and interesting analytical structure. The leading twist leading order amplitude is proportional to valence quark generalized parton distributions taken at the border value $x=\pm \xi$. Cross section estimates show that this process is measurable at JLab energies. The angular asymmetry triggered by a linearly polarized photon beam is large.