Centrality dependence of charged hadron production in deuteron+gold and nucleon+gold collisions at sqrt(s_NN)=200 GeV

TL;DR

This study measures charged hadron spectra in deuteron-gold and nucleon-gold collisions at 200 GeV, revealing saturation of yields per nucleon-nucleon collision at high momentum and analyzing particle ratios across centralities.

Contribution

It provides detailed spectra and yield analysis as a function of collision centrality and introduces a method to select nucleon-gold events via forward rapidity tagging.

Findings

Charged hadron yields per nucleon-nucleon collision saturate at high p_T.

Charged hadron to neutral pion ratios are characterized as a function of p_T.

Spectra vary with collision centrality and number of binary collisions.

Abstract

We present transverse momentum (p_T) spectra of charged hadrons measured in deuteron-gold and nucleon-gold collisions at \sqrts = 200 GeV for four centrality classes. Nucleon-gold collisions were selected by tagging events in which a spectator nucleon was observed in one of two forward rapidity detectors. The spectra and yields were investigated as a function of the number of binary nucleon-nucleon collisions, \nu, suffered by deuteron nucleons. A comparison of charged particle yields to those in p+p collisions show that the yield per nucleon-nucleon collision saturates with \nu for high momentum particles. We also present the charged hadron to neutral pion ratios as a function of p_T.