Transverse-Momentum and Collision-Energy Dependence of High-${p}_{T}$ Hadron Suppression in $\mathrm{A}\mathrm{u}+\mathrm{A}\mathrm{u}$ Collisions at Ultrarelativistic Energies

Transverse-Momentum and Collision-Energy Dependence of High- $p_{T}$ Hadron Suppression in $A u + A u$ Collisions at Ultrarelativistic Energies

J. Adams et al. (STAR Collaboration)

Phys. Rev. Lett. 91, 172302 – Published 22 October 2003

Abstract

We report high statistics measurements of inclusive charged hadron production in $A u + A u$ and $p + p$ collisions at $\sqrt{s_{N N}} = 200 G e V$ . A large, approximately constant hadron suppression is observed in central $A u + A u$ collisions for $5 < p_{T} < 12 G e V / c$ . The collision energy dependence of the yields and the centrality and $p_{T}$ dependence of the suppression provide stringent constraints on theoretical models of suppression. Models incorporating initial-state gluon saturation or partonic energy loss in dense matter are largely consistent with observations. We observe no evidence of $p_{T}$ -dependent suppression, which may be expected from models incorporating jet attenuation in cold nuclear matter or scattering of fragmentation hadrons.