Diffractive processes at the LHC within $k_t$ -factorization approach

TL;DR

This paper introduces a novel $k_t$-factorization approach to study single diffractive production of charm pairs at the LHC, revealing larger cross sections and new correlation observables compared to traditional methods.

Contribution

First application of $k_t$-factorization to diffractive processes at the LHC, incorporating unintegrated diffractive PDFs and comparing with collinear approaches.

Findings

$k_t$-factorization yields larger cross sections.

New correlation observables for charm pairs are presented.

Effective inclusion of higher-order effects in the new approach.

Abstract

We discuss the single diffractive production of $c \bar c$ pairs and charmed mesons at the LHC. In addition to standard collinear approach, for a first time we propose a $k_t$-factorization approach to the diffractive processes. The transverse momentum dependent (the unintegrated diffractive parton distributions) in proton are obtained with the help of the Kimber-Martin-Ryskin prescription where collinear diffractive PDFs are used as input. In this calculation the transverse momentum of the pomeron is neglected with respect to transverse momentum of partons entering the hard process. The results of the new approach are compared with those of the standard collinear one. Significantly larger cross sections are obtained in the $k_t$-factorization approach where some part of higher-order effects is effectively included. Some correlation observables, like azimuthal angle correlation between $c$ and $\bar c$, and $c \bar c$ pair transverse momentum distribution were obtained for the first time.