When invariable cross-sections change: the Electron-Ion Collider case

TL;DR

This paper investigates how the bremsstrahlung cross-section varies at the Electron-Ion Collider due to lateral beam displacements, revealing significant effects and linking them to quantum phenomena over macroscopic distances.

Contribution

It introduces a novel approach to study bremsstrahlung cross-section variations using beam displacements at the EIC, challenging the assumption of fixed cross-sections.

Findings

Strong increase in observed cross-sections at large beam separations

Identification of quantum effects over macroscopic distances

Evaluation of coherent bremsstrahlung properties at the EIC

Abstract

In everyday research, it is tacitly assumed that the scattering cross-sections have fixed values for the given particle species, centre-of-mass energy, and particle polarizations. However, this assumption has been called into question after several observations of suppression of high-energy bremsstrahlung. This process will play a major role in experiments at the future Electron-Ion Collider, and we show here how variations of the bremsstrahlung cross-section can be profoundly studied there using the lateral beam displacements. In particular, we predict very strong increase of the observed cross-sections for large beam separations. We also discuss the relation of these elusive effects to other quantum phenomena occurring over macroscopic distances. In this context, spectacular and possibly useful properties of the coherent bremsstrahlung at the EIC are also evaluated.