DbarD and DD pair production at the LHCb in the parton Reggeization approach

TL;DR

This paper investigates DbarD and DD pair production at the LHC using the parton Reggeization approach, successfully describing various distributions without free parameters, and employing Reggeized amplitudes and unintegrated gluon distributions.

Contribution

It introduces a novel application of the parton Reggeization approach with universal scale-dependent fragmentation functions to describe heavy meson pair production at the LHC.

Findings

Accurately describes azimuthal, transverse momentum, rapidity, and invariant mass distributions.

Uses Reggeized amplitudes based on Lipatov effective theory.

Employs Kimber-Martin-Ryskin model for gluon distributions.

Abstract

We study the inclusive DbarD and DD pair production in proton-proton collisions at the LHC at lead- ing order of the parton Reggeization approach endowed with universal scale-depended fragmen- tation functions for c-quark to D-meson and for gluon to D-meson transitions. We have described DbarD and DD distributions in azimuthal angle, as well as transverse momentum, rapidity distance, and invariant mass measured in the region of large rapidity 2 < y < 4 by the LHCb Collabora- tion at the LHC without free parameters. We have used Reggeized amplitudes for the processes RR - gg and RR - c barc which are obtained accordingly to Feynman rules of the L.N. Lipatov effective theory of Reggeized partons, and Kimber-Martin-Ryskin model for unintegrated gluon distribution function in a proton with Martin-Stirling-Thorne-Watt collinear parton distributions as inputs.