Single Particle Probes of d+Au Collisions in PHENIX

TL;DR

This paper investigates the nuclear structure and gluonic content of gold nuclei in d+Au collisions at RHIC by measuring the nuclear modification factor and particle correlations across rapidities to understand cold nuclear matter effects.

Contribution

It introduces new measurements of R_{dAu} and hadron correlations at forward rapidities to probe gluon saturation and cold nuclear matter effects in d+Au collisions.

Findings

Measurement of R_{dAu} in new forward rapidity regions.

Evidence of gluon saturation effects from hadron correlations.

Insights into cold nuclear matter effects in d+Au collisions.

Abstract

Deuteron-gold collisions provide insights into the nuclear structure function and a valuable baseline for Au+Au collisions. Measurement of the nuclear modification factor, R_{dAu}, in d+Au in the PHENIX central arms for hadrons and photons allows us to disentangle cold nuclear matter effects from the hot medium effects that are important in Au+Au collisions. In addition, the d+Au system can yield important insights into the gluonic structure of the Au nucleus. RHIC experiments have previously measured suppression of forward rapidity particle production relative to p+p scaled by the number of binary N-N collisions, but a definitive explanation of these data is thus far elusive. Correlations between hadrons with a large rapidity gap are a particularly sensitive probe of gluon saturation. We will discuss probing this physics via particle production in events tagged with high momentum particles at different rapidities, along with R_{dAu} in new forward rapidity regions.