Related papers: Charm production in diffractive DIS and PHP at ZEU…
The study of heavy flavor production is a central topic of research at HERA and is an important testing ground for perturbative QCD. A selection of results for charm and beauty production in gamma p, using different experimental techniques…
In the ZEUS experiment at HERA, photoproduction processes have been studied for photon-proton centre-of-mass energies in the range 100 < W_gamma p < 300 GeV and jet transverse energies extending to E_T^jet ~ 70 GeV. The data contribute to…
$D^{*+/-}$ production in the diffractive interactions was measured with the ZEUS detector at HERA using integrated luminosities of 44 pb$^{-1}$ in deep inelastic scattering and 38 pb$^{-1}$ in photoproduction processes. Diffractive…
The results of measurement of beauty quark production at HERA performed by the H1 and ZEUS collaborations are presented. Total cross sections and the differential cross sections have been measured in both the photoproduction and the deep…
Recent results from ZEUS for inclusive jet cross sections, dijet cross sections and dijet angular distributions are compared with NLO perturbative QCD calculations. The observation of isolated high $P_T$ photons (prompt photons) is also…
The H1 and ZEUS collaborations at HERA report new data on the diffractive production of vector mesons with a many-fold increase of luminosity compared to previous measurements. The new data include photoproduction and electroproduction of…
Charm production is studied in deep-inelastic electron-photon scattering using OPAL data at e+e- centre-of-mass energies from 183 to 209 GeV. Charm quarks are identified by exclusive reconstruction of D* mesons. The cross-section of D*…
We present a calculation of diffractive charm jet production at hadron colliders in perturbative QCD based on the two-gluon exchange model. Differing from the previous calculations, we abandon the use of the effective color-singlet vitual…
We demonstrate that perturbative QCD allows one to calculate the absolute cross section of diffractive exclusive production of photons at large $Q^2$ at HERA, while the aligned jet model allows one to estimate the cross section for…
Recent data on diffractive photoproduction of dijets are analyzed within the framework of fracture functions and paying special attention to the consequences of the use of different rapidity gap definitions in order to identify diffractive…
Heavy quarks, such as charm and beauty, possess masses significantly larger than the characteristic energy scale of Quantum Chromodynamics (QCD), and are thus predominantly produced in hard-scattering processes with large momentum transfer…
The $p_{\rm T}$-differential production cross sections of the prompt (B feed-down subtracted) charmed mesons D$^0$, D$^+$, and D$^{*+}$ in the rapidity range $|y|<0.5$, and for transverse momentum $1< p_{\rm T} <12$ GeV/$c$, were measured…
Diffractive photoproduction of dijets was measured with the ZEUS detector at the ep collider HERA using an integrated luminosity of 77.2 pb-1. The measurements were made in the kinematic range Q^2 < 1 GeV^2, 0.20 < y < 0.85 and x_pom <…
New results on charm and beauty electroproduction from the H1 and ZEUS Collaborations at the ep collider HERA are presented. Differential cross sections are compared to a next-to-leading order QCD calculation. The heavy quark contributions,…
We discuss single diffractive gauge bosons ($\gamma^*,\,W^{\pm},\,Z$) production in proton-proton collisions at different (LHC and RHIC) energies within the color dipole approach. The calculations are performed for gauge bosons produced at…
We present a perturbative QCD calculation of diffractive $D_s$ production in charged current deep inelastic scattering. In the two-gluon exchange model, we analyze the diffractive process $\nu N \to \mu^- N \Ds$, which may provide useful…
A measurement of charm and beauty photoproduction at the electron proton collider HERA is presented based on the simultaneous detection of a D*^{\pm} meson and a muon. The correlation between the D* meson and the muon serves to separate the…
The current analysis aims to present the results of a QCD analysis of diffractive parton distribution functions (diffractive PDFs) at next-to-leading order (NLO) accuracy in perturbative QCD. In this new determination of diffractive PDFs,…
Measurements of $D^{*}(2010)$ meson production in diffractive deep inelastic scattering $(5<Q^{2}<100~{\rm GeV}^{2})$ are presented which are based on HERA data recorded at a centre-of-mass energy $\sqrt{s} = 319{\rm~GeV}$ with an…
We use perturbative QCD, beyond the leading $\ln Q^2$ approximation, to show how measurements of diffractive $J/\psi$ production at HERA can provide a sensitive probe of the gluon density of the proton at small values of Bjorken $x$. We…