Cold Nuclear Matter Effects in d+Au Collisions at PHENIX

TL;DR

This paper investigates initial state effects in d+Au collisions at RHIC by measuring various particles and comparing results to nuclear parton distribution function predictions, aiding the understanding of cold nuclear matter effects.

Contribution

It provides new measurements of pi0, eta, jets, and heavy-flavor decay electrons in d+Au collisions, offering insights into initial state modifications in heavy-ion physics.

Findings

Data show modifications consistent with nuclear PDFs

Results help disentangle initial state effects from hot medium effects

Provides baseline for interpreting heavy-ion collision results

Abstract

To interpret the measurements in heavy-ion collisions at the Relativistic Heavy-Ion Collider (RHIC) it is crucial to understand the initial state of the colliding gold (Au) nuclei. The parton distribution in Au nuclei is modified compared to protons, and their isospin composition is different due to the presence of neutrons. d+Au collisions at RHIC at the same collision energies are an important tool to study initial state modifications. PHENIX has measured pi0, eta, and reconstructed jets at high transverse momentum. These data are compared to predictions from nuclear parton distribution functions. Furthermore, single electrons from heavy-flavor decays have been measured by PHENIX.