Double-parton scattering effects in associated production of charm mesons and dijets at the LHC

TL;DR

This paper investigates the production of charm mesons and dijets at the LHC, demonstrating that double-parton scattering significantly dominates over single-parton scattering in certain phase space regions, with distinct observable signatures.

Contribution

It provides the first detailed analysis of DPS effects in charm and dijet production at the LHC using the $k_T$-factorization approach with unintegrated parton distributions.

Findings

DPS dominates over SPS in many phase space regions.

Transition from DPS to SPS dominance observed with increasing transverse momentum.

Distinct azimuthal correlation patterns predicted for different production mechanisms.

Abstract

We calculate several differential distributions for the production of charm and dijets. Both single-parton scattering (SPS) and double-parton scattering (DPS) contributions are calculated in the $k_T$-factorization approach. The Kimber-Martin-Ryskin unintegrated parton distributions are used in our calculations. Relatively low cuts on jet transverse momenta are imposed to enhance the double-parton scattering mechanism contribution. We find dominance of the DPS contribution over the SPS one. We have found regions of the phase space where the SPS contribution is negligible compared to the DPS contribution. The distribution in transverse momentum of charm quark/antiquark or charmed mesons can be used to observe transition from the dominance of DPS at low transvsverse momenta to the dominance of SPS at large transverse momenta. Very distinct azimuthal correlation patterns (for $c \bar{c}$, $c\mathrm{\textit{-jet}}$, $\mathrm{\textit{jet-jet}}$, $D^0\mathrm{\textit{-jet}}$, $D^0 D^0$) are predicted as a result of the competition of the SPS and DPS mechanisms.