Unveiling the nuclear structure at small x using azimuthal correlations in dA collisions

TL;DR

This paper investigates azimuthal correlations in high-energy dA collisions at RHIC, emphasizing the importance of finite rapidity differences and transverse momentum dependence to accurately describe experimental data, supporting Color Glass Condensate models.

Contribution

It demonstrates that realistic azimuthal correlation functions require accounting for finite rapidity differences and transverse momentum dependence, advancing understanding of nuclear structure at small x.

Findings

Depletion of back-to-back correlations in central dAu collisions forward direction.

Inadequacy of leading logarithmic approximation for experimental data.

Support for Color Glass Condensate predictions.

Abstract

We discuss azimuthal correlations in double inclusive hadron production in high energy $dA$ collisions at RHIC. We argue that the leading logarithmic approximation is inadequate for description of experimental data. Realistic shape of the azimuthal correlation function is obtain only if we keep terms that are finite in the rapidity difference between the produced hadrons. Likewise, transverse momentum dependence of parton distribution functions in both deuteron and nucleus must be retained. We observe depletion of the back-to-back correlations in central $dAu$ collisions in the forward direction consistent with the Color Glass Condensate predictions.