Baryon stopping and charge deposition in heavy-ion collisions due to gluon saturation

TL;DR

This paper uses the Color Glass Condensate effective field theory to analyze baryon stopping and charge deposition in high-energy heavy-ion collisions, providing analytical predictions and validation against experimental data across a wide energy range.

Contribution

It introduces a simplified phenomenological formula for charge deposition and an analytical prediction for the baryon stopping parameter, validated with experimental data and the McDIPPER framework.

Findings

Excellent agreement of $oldsymbol{ ext{alpha}_B}$ with experimental data.

Derived a parametrical dependence of charge deposition on energy and geometry.

Validated results across collision energies from 62.4 to 5020 GeV.

Abstract

We compute baryon and electric charge deposition in high-energy heavy-ion collisions using the Color Glass Condensate (CGC) Effective Field Theory, where at leading order charge is deposited through multiple scatterings of valence quarks with a saturated gluon target. A simplified phenomenological formula is derived to describe charge deposition, from which the parametrical dependence with collisional energy and geometry can be extracted. We present an approximate analytical prediction of the so-called baryon stopping parameter $\alpha_B$, which shows excellent agreement with the state-of-the art extractions of $\alpha_B$ from experimental data. These results are further validated using the McDIPPER framework, by computing charge deposition at midrapidity across a range of collision energies ($\sqrt{s_{\rm NN}}= 62.4 - 5020$ GeV).