Exploring the Collective Phenomenon at the Electron-Ion Collider

TL;DR

This paper investigates collective phenomena in electron-ion collisions at the EIC, linking high multiplicity events to initial state interactions and providing predictions for long-range correlations using the Color Glass Condensate model.

Contribution

It introduces a novel approach to study collectivity in eA collisions at the EIC, connecting it to phenomena observed in pA and photo-nuclear collisions, and offers quantitative predictions.

Findings

Initial state interactions explain azimuthal correlations in photo-nuclear collisions.

Predictions for long-range correlations in eA collisions at the EIC.

EIC's high precision enables detailed exploration of collective phenomena.

Abstract

Based on rare fluctuations in strong interactions, we argue that there is a strong physical resemblance between the high multiplicity events in photo-nuclear collisions and those in $pA$ collisions, in which interesting long range collective phenomena are discovered. This indicates that the collectivity can also be studied in certain kinematic region of the upcoming Electron-Ion Collider (EIC) where the incoming virtual photon has a sufficiently long lifetime. Using a model in the Color Glass Condensate formalism, we first show that the initial state interactions can explain the recent ATLAS azimuthal correlation results measured in the photo-nuclear collisions, and then we provide quantitative predictions for the long range correlations in $eA$ collisions in the EIC regime. With the unprecedented precision and the ability to change the size of the collisional system, the high luminosity EIC will open a new window to explore the physical mechanism responsible for the collective phenomenon.