Interparticle correlations in the production of J/\psi pairs in proton-proton collisions

TL;DR

This paper investigates methods to distinguish single and double parton scattering contributions in J/psi pair production at the LHC, emphasizing the potential of rapidity difference measurements over azimuthal correlations.

Contribution

It provides a detailed comparison of SPS and DPS production mechanisms, including higher-order corrections, and evaluates the effectiveness of different kinematic variables for disentangling these modes.

Findings

Disentangling SPS and DPS via azimuthal correlations is challenging.

Rapidity difference may be a more effective discriminator with sufficient detector acceptance.

Higher-order corrections influence the shape of differential cross sections.

Abstract

We focus on the problem of disentangling the single (SPS) and double (DPS) parton scattering modes in the production of \J pairs at the LHC conditions. Our analysis is based on comparing the shapes of the differential cross sections and on studying their behavior under imposing kinematical cuts. On the SPS side, we consider the leading-order ${\cal O}(\alpha_s^4)$ contribution with radiative corrections (taken into account in the framework of the \ktf approach) and the subleading ${\cal O}(\alpha_s^6)$ contribution from \pd ~gluon-gluon scattering represented by one gluon exchange and two gluon exchange mechanisms. We come to the conclusion that disentangling the SPS and DPS modes is rather difficult on the basis of azimuthal correlations, while the rapidity difference looks more promising, provided the acceptance of the experimental detectors has enough rapidity range.