Related papers: Open charm production in diffractive ep collisions
We have calculated the diffractive dijet cross section in low-Q^2 ep scattering in the HERA regime. The results of the calculation in LO and NLO are compared to recent experimental data of the H1 collaboration. We find that in LO the…
We have calculated the diffractive dijet cross section in low-Q^2 ep scattering in the HERA regime. The results of the calculation in LO and NLO are compared to recent experimental data of the H1 collaboration. We find that in LO the…
The total hadronic gamma*gamma* cross sections at high energy are calculated as a function of energy and photon virtuality in a model combining Regge exchange, the quark box diagram (a fixed pole in Regge language) and soft and hard pomeron…
We calculate the inclusive and diffractive photoproduction of heavy quarks in proton-proton collisions at Tevatron and LHC energies, where the photon reaches energies larger than those ones accessible at DESY-HERA. The integrated cross…
A study of double charmed meson production in proton-proton and proton-nucleus collisions at the LHC energies is performed. Based on the color dipole formalism developed in the transverse momentum representation and the double parton…
The first observation of open b production in ep collisions is reported. An event sample containing muons and jets has been selected which is enriched in semileptonic b quark decays. The visible cross section \sigma(ep -> b \bar{b}X -> \mu…
The structure of real and virtual photons has been studied in ep collisions at HERA using dijet production. Measurements of differential dijet cross sections as function of the fraction of photon's momentum invested in the dijet system are…
We discuss diphoton semi(exclusive) production in ultraperipheral $PbPb$ collisions at energy of $\sqrt{s_{NN}}=$ 5.5 TeV (LHC). The nuclear calculations are based on equivalent photon approximation in the impact parameter space. The cross…
The cross section for deeply virtual Compton scattering in the reaction ep -> e gamma p has been measured with the ZEUS detector at HERA using integrated luminosities of 95.0 pb-1 of e+p and 16.7 pb-1 of e-p collisions. Differential cross…
The way a charm-quark fragments into a charmed hadron is a challenging problem both for the theoretical and the experimental particle physics. Moreover, in neutrino induced charm-production, peculiar processes occur such as quasi-elastic…
We investigate the charm hadron production in relativistic heavy-ion collisions with the quark combination model. The $p_{T}$ dependencies of the charm baryon to meson ratios such as…
In this report diffractive high energy reactions are discussed in a functional integral approach where hadronic amplitudes are calculated from vacuum expectation values of lightlike Wegner-Wilson loops. In the first part we calculate…
We have calculated the next-to-leading order cross sections for the inclusive production of D* mesons in gamma-p collisions at HERA in two approaches using massive or massless charm quarks. The usual massive theory for the direct cross…
We discuss charm production at LHC. The production of single $c \bar c$ pairs is calculated in the $k_t$-factorization approach. We use several unintegrated gluon distributions from the literature. The hadronization is included with the…
We study the diffractive production of photons in gamma-p and gamma-gamma collisions. We specifically compute the rates for gamma*-p -> gamma-X and for gamma*-gamma* -> gamma-gamma, where X denotes the proton dissociation. We focus on the…
We estimate the differential and total cross sections for both the photoproduction of vector D*-meson and its yield in deep inelastic scattering at the HERA collider in the framework of model motivated by perturbative calculations in QCD.…
We discuss production of charmed mesons as well as electrons/muons from semileptonic decays of charm and bottom mesons in proton-proton collisions at the LHC. The cross section for inclusive production of $c \bar c$ and $b \bar b$ pairs is…
We derive the forward photoproduction amplitude for the diffractive $\gamma p \to l^+ l^- p$ reaction in the momentum space. within the formalism of $k_\perp$- factorization. Predictions for the $\gamma p \to l^+ l^- p$ reaction are given…
A measurement of charm and beauty dijet photoproduction cross sections at the ep collider HERA is presented. Events are selected with two or more jets of transverse momentum $p_t^{jet}_{1(2)}>11(8)$ GeV in the central range of…
Recent experimental results on the partonic structure of the photon and on the color singlet exchange in strong interaction processes are reviewed. At the LEP electron-positron and HERA lepton-proton colliders, complementary and consistent…