Transverse-Momentum Dependence of the J/psi Nuclear Modification in d+Au Collisions at sqrt(s_NN)=200 GeV

TL;DR

This study measures J/psi production in d+Au collisions at 200 GeV, revealing how nuclear effects depend on transverse momentum, rapidity, and collision centrality, with notable suppression and enhancement patterns.

Contribution

It provides detailed transverse momentum and rapidity dependence of J/psi nuclear modification factors in d+Au collisions at 200 GeV, highlighting impact parameter effects.

Findings

Suppression of J/psi at low p_T and positive rapidity.

Enhancement of J/psi at high p_T and negative rapidity.

Largest modification observed in central collisions.

Abstract

We present measured J/psi production rates in d+Au collisions at sqrt(s_NN) = 200 GeV over a broad range of transverse momentum (p_T=0-14 GeV/c) and rapidity (-2.2<y<2.2). We construct the nuclear-modification factor R_dAu for these kinematics and as a function of collision centrality (related to impact parameter for the R_dAu collision). We find that the modification is largest for collisions with small impact parameters, and observe a suppression (R_dAu<1) for p_T<4 GeV/c at positive rapidities. At negative rapidity we observe a suppression for p_T<2 GeV/c then an enhancement (R_dAu>1) for p_T>2 GeV/c. The observed enhancement at negative rapidity has implications for the observed modification in heavy-ion collisions at high p_T.