D* Meson Production in Deep-Inelastic Diffractive Interactions at HERA

TL;DR

This paper reports the first measurement of D* meson production cross section in diffractive deep-inelastic scattering at HERA, providing insights into the underlying QCD processes and the role of gluons in diffraction.

Contribution

It presents the first experimental measurement of D* meson production in diffractive DIS at HERA, comparing results with QCD-based theoretical models.

Findings

Cross section for D* production is 246+-54+-56 pb.

D* mesons constitute about 6% of inclusive D* cross section.

Data indicates a significant contribution from Boson-Gluon-Fusion at low z_pom^obs.

Abstract

A measurement is presented of the cross section for D* meson production in diffractive deep-inelastic scattering for the first time at HERA. The cross section is given for the process ep -> eXY, where the system X contains at least one D* meson and is separated by a large rapidity gap from a low mass proton remnant system Y. The cross section is presented in the diffractive deep-inelastic region defined by 2< Q^2 < 100 GeV^2, 0.05 < y < 0.7, x_pom < 0.04, M_Y < 1.6 GeV and |t| < 1 GeV^2. The D* mesons are restricted to the range ptD* > 2 GeV and |\eta_D* | < 1.5. The cross section is found to be 246+-54+-56 pb and forms about 6% of the corresponding inclusive D* cross section. The cross section is presented as a function of various kinematic variables, including z_pom^obs which is an estimate of the fraction of the momentum of the diffractive exchange carried by the parton entering the hard-subprocess. The data show a large component of the cross section at low z_pom^obs where the contribution of the Boson-Gluon-Fusion process is expected to dominate. The data are compared with several QCD--based calculations.