Light nuclei photoproduction in relativistic heavy ion ultraperipheral collisions

TL;DR

This paper investigates light nuclei pair photoproduction in relativistic heavy ion ultraperipheral collisions using a quantum electrodynamics model, providing detailed distributions and modulation patterns of proton-antiproton pairs.

Contribution

It introduces a quantum electrodynamics approach with wave-packet description to compute photoproduction cross sections and analyze azimuthal modulations in ultraperipheral collisions.

Findings

Observed a cos(2φ) modulation in azimuthal distribution

Found negligible cos(4φ) modulation

Provided transverse momentum and invariant mass distributions

Abstract

We have investigated light nuclei pair photoproduction in relativistic heavy ion ultraperipheral collisions. As a first attempt, we employ our previously developed quantum electrodynamics model, which incorporates a wave-packet description of initial nuclei, to compute the cross section for proton-antiproton pair photoproduction. The effective vertex for the photon and proton interaction is chosen based on studies of two-photon exchange effects in hadron physics. We present the transverse momentum, invariant mass, and azimuthal angle distributions of proton-antiproton pairs at $\sqrt{s_{NN}}=200$ GeV in Au+Au ultraperipheral collisions. We observe a $\cos(2\phi)$ modulation and an almost negligible $\cos(4\phi)$ modulation in the azimuthal angle distribution. Our studies helps us better understand the matter generated by light.