Collective effects in light-heavy ion collisions

TL;DR

This paper investigates azimuthal anisotropies in various light-heavy ion collisions using a hydrodynamic model, comparing results with experimental data and providing predictions for future experiments.

Contribution

It applies the IP-Glasma+MUSIC model to analyze azimuthal anisotropies across multiple collision systems and energies, highlighting model successes and limitations.

Findings

Elliptic and triangular anisotropies in peripheral Pb+Pb are well described.

Underestimation of anisotropies in p+Pb suggests missing initial state correlations.

Predictions for azimuthal anisotropies in p+Au, d+Au, and He3+Au at 200 GeV are provided.

Abstract

We present results for the azimuthal anisotropy of charged hadron distributions in A+A, p+A, d+A, and He3+A collisions within the IP-Glasma+MUSIC model. Obtained anisotropies are due to the fluid dynamic response of the system to the fluctuating initial geometry of the interaction region. While the elliptic and triangular anisotropies in peripheral Pb+Pb collisions at root-s=2.76 TeV are well described by the model, the same quantities in root-s=5.02 TeV p+Pb collisions underestimate the experimental data. This disagreement can be due to neglected initial state correlations or the lack of a detailed description of the fluctuating spatial structure of the proton, or both. We further present predictions for azimuthal anisotropies in p+Au, d+Au, and He3+Au collisions at root-s=200 GeV. For d+Au and 3He+Au collisions we expect the detailed substructure of the nucleon to become less important.