Related papers: Heavy quark coefficient functions at asymptotic va…
We compare the numerical predictions of the k_T-factorization approach (semihard theory) for heavy quark production in high energy nucleon-nucleon and photon-nucleon collisions with the experimental data from Tevatron-collider and HERA.…
In this contribution we report on the calculations of heavy-quark photoproduction using the semihard approach, emphasizing the results obtained with the phenomenological saturation model.
The double coherent and non-coherent diffractive production of heavy quark - antiquark pairs ($Q \bar{Q}$) in heavy ion scattering at high energies (LHC) is considered. The total and differential cross sections of these processes with the…
We present details on calculation of next-to-next-to-leading order QCD corrections to massive charged-current coefficient functions in deep-inelastic scattering. Especially we focus on the application to charm-quark production in neutrino…
We calculate the massive two--loop pure singlet Wilson coefficients for heavy quark production in the unpolarized case analytically in the whole kinematic region and derive the threshold and asymptotic expansions. We also recalculate the…
We study the production of photons accompanied by jets in large-Q2 deep inelastic scattering. Numerical results for the cross section differential with respect to the fraction of momentum z_gamma carried by a photon inside a jet at large…
We calculate the QED corrections to deep inelastic scattering with tagged photons at HERA in the leading logarithmic approximation. Due to the special experimental setup, two large scales appear in the calculation that lead to two large…
Charm production in deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 82 pb^{-1}. Charm has been tagged by reconstructing D^{*+}, D^0, D^{+} and D_s^+ (+ c.c.) charm mesons. The…
The import of HERA data on heavy quark production for LHC experiments is discussed. Knowlegde of all aspects of the beauty and charm production process, viz. the parton density functions of colliding hadrons, the hard scatter, and the…
Using the "Quality Factor" (QF) method, we analyse the scaling properties of deep-inelastic processes at HERA and fixed target experiments for x<10^{-2}.
Jet event rates in deep inelastic ep scattering at HERA are investigated applying the modified JADE jet algorithm. The analysis uses data taken with the H1 detector in 1994 and 1995. The data are corrected for detector and hadronization…
We calculate the photoproduction of heavy quarks in proton-proton collisions at RHIC, Tevatron and LHC energies. The integrated cross section and the rapidity distributions for open charm and bottom production are computed employing sound…
The proton structure function F_2(x,Q^2) is measured in inelastic QED Compton scattering using data collected with the H1 detector at HERA. QED Compton events are used to access the kinematic range of very low virtualities of the exchanged…
Nuclear modification of hadron production in deep inelastic lepton-nucleus scattering can be applied to study the parton propagation mechanism in cold nuclear matter. By means of the analytic parameterization of quenching weight based on…
We consider gluonic contributions to the heavy flavor Wilson coefficients at 3-loop order in QCD with two heavy quark lines in the asymptotic region $Q^2 \gg m_{1(2)}^2$. Here we report on the complete result in the case of two equal masses…
We present the first full analytic evaluation of the scattering amplitude for the process $q {\bar q} \to Q {\bar Q}$ up-to two loops in Quantum Chromodynamics, for a massless $(q)$ and a massive $(Q)$ quark flavour. The interference terms…
In this letter we extend the factorization procedure of the deep-inelastic hadron tensor, proposed by Qiu, to include non-zero quark masses. The manifest gauge invariance of both soft and hard parts is preserved. Using a so-called spurion…
Results are presented on the production of isolated prompt photons in photoproduction (virtuality Q^2 < 1 GeV^2) and in deep inelastic scattering (Q^2 > 35 GeV^2). The results are reasonably well described by pQCD calculations in next to…
The electromagnetic and weak structure functions of the photon can be studied in the deep inelastic electron-photon processes e+gamma -> e+X and e+gamma -> nu+X. While at low energies only virtual photon exchange is operative in the…
We give predictions for the leading order amplitudes for deeply virtual Compton scattering and hard meson electroproduction reactions at large Q^2 in the valence region in terms of skewed quark distributions. We give first estimates for the…