Pseudorapidity dependence of particle production and elliptic flow in asymmetric nuclear collisions of $p$$+$Al, $p$$+$Au, $d$$+$Au, and $^{3}$He$+$Au at $\sqrt{s_{_{NN}}}=200$ GeV

TL;DR

This study investigates particle production and elliptic flow in asymmetric nuclear collisions at 200 GeV, providing data that challenge and refine existing models of particle emission and flow dynamics.

Contribution

It offers comprehensive measurements of charged hadron production and elliptic flow across various asymmetric collision systems, testing the wounded quark model's applicability.

Findings

Wounded quark model successfully describes the data

Charged hadron production varies with pseudorapidity and multiplicity

Elliptic flow $v_2$ measurements constrain particle emission models

Abstract

Asymmetric nuclear collisions of $p$$+$Al, $p$$+$Au, $d$$+$Au, and $^{3}$He$+$Au at $\sqrt{s_{_{NN}}}=200$ GeV provide an excellent laboratory for understanding particle production, as well as exploring interactions among these particles after their initial creation in the collision. We present measurements of charged hadron production $dN_{\rm ch}/d\eta$ in all such collision systems over a broad pseudorapidity range and as a function of collision multiplicity. A simple wounded quark model is remarkably successful at describing the full data set. We also measure the elliptic flow $v_{2}$ over a similarly broad pseudorapidity range. These measurements provide key constraints on models of particle emission and their translation into flow.