Parton Rescatterings in Large-x Nuclear Suppression at RHIC

TL;DR

This paper explains the suppression of high-pT hadron production at forward rapidities in d+Au collisions at RHIC as due to parton rescatterings, supported by calculations matching experimental data and challenging saturation-based models.

Contribution

It introduces a light-cone dipole approach to quantitatively describe nuclear suppression, emphasizing parton rescatterings over saturation effects.

Findings

Good agreement with BRAHMS and STAR data

Prediction of nuclear suppression at midrapidities

Exclusion of Color Glass Condensate models for observed suppression

Abstract

We demonstrate that strong suppression of the relative production rate (d+Au)/(p+p) of inclusive high-pT hadrons at forward rapidities observed at RHIC is due to parton multiple rescatterings in nuclear matter. The light-cone dipole approach-based calculations are in a good agreement with BRAHMS and STAR data. They also indicate a significant nuclear suppression at midrapidities with a weak onset of the coherence effects. This prediction is supported by the preliminary d+Au data from the PHENIX Collaboration. Moreover, since similar suppression pattern is also expected to show up at lower energies where effects of parton saturation are not expected, we are able to exclude from the interpretation of observed phenomena models based on the Color Glass Condensate.