相关论文: Charm as a Key to Diffractive Processes
Charm production as related to the determination of the strange sea density in deep inelastic charged current processes is studied predominantly in the framework of the $\overline{{\rm{MS}}}$ fixed flavor factorization scheme. Perturbative…
Inclusive charm meson production cross sections in the deep inelastic scattering and photoproduction regimes are compared with QCD leading and next-to-leading (NLO) calculations. The NLO predictions are significantly below the data in some…
Diffraction is an old subject which has received much interest in recent years due to the advent of diffractive hard scattering. We discuss some theoretical models and experimental results that have shown new striking effects, e.g. rapidity…
We use perturbative QCD to calculate the cross sections $\sigma^{L,T}$ for the diffractive production of open charm $(c\overline{c})$ from longitudinally and transversely polarised photons (of virtuality $Q^2$) incident at high energy…
The production of particles with double, triple and hidden charm in heavy ion collisions is studied in the framework of the statistical coalescence model. According to the postulates of the model, the charm quark-antiquark pairs are created…
We study the relative contribution of partonic sub-processes to D meson production and D meson-triggered inclusive di-hadrons to lowest order in perturbative QCD. While gluon fusion dominates the creation of large angle DD-bar pairs, charm…
At high center of mass energies, hadroproduction of heavy quarks can be expressed in terms of the same color dipole cross section as low Bjorken-x deep inelastic scattering. We show analytically that at leading order, the dipole formulation…
We present a fully differential next-to-next-to-leading order calculation of charm quark production in charged-current deep-inelastic scattering, with full charm-quark mass dependence. The next-to-next-to-leading order corrections in…
We compare different schemes for the treatment of heavy quark production in Deep-Inelastic Scattering (DIS). For fully-integrated quantities such as $F_{2}(x,Q^{2})$, we advocate the use of the General-Massive Variable-Flavor-Number…
We demonstrate that the global properties of the ``rapidity gap'' events, observed at HERA, can be understood based on electron-gluon scattering as the underlying partonic process. Using the measured inclusive structure function $F_2$ to…
We present predictions for the diffractive production of heavy quarks in deep-inelastic scattering and hadron-hadron collisions and for double diffractive dijet production in hadron-hadron collisions. With the assumption of hard scattering…
Order $\alpha_s$-corrections to the diffractive structure functions $F_L^D$ and $F_2^D$ at large $Q^2$ and small $x$ are evaluated in the semiclassical approach, where the initial proton is treated as a classical colour field. The…
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 describe diffractive deeply inelastic scattering in terms of diffractive parton distributions. We investigate these distributions in a hamiltonian formulation that emphasizes the spacetime picture of diffraction scattering. For hadronic…
We outline the existing descriptions of the charm component of the deep inelastic proton structure function F2. We discuss recent approaches to include charm mass effects in the parton evolution equations and the coefficient functions.
Recent experiments at Fermilab and CERN have observed a strong asymmetry between the hadroproduction cross sections of leading $D$ mesons, containing projectile valence quarks, and nonleading charmed mesons, without projectile valence…
On the basis of the experimental data on diffractive processes in $\pi p$, $pp$ and $p \bar p$ collisions at intermediate, moderately high and high energies, we restore the scattering amplitude related to the $t$-channel exchange by vacuum…
The cross section for the diffractive reaction gamma* + p -> c cbar + p with a real or virtual photon is calculated in the nonperturbative two-gluon exchange model of Landshoff and Nachtmann. Numerical predictions are given for cross…
We present a theoretical framework to study open charm production in relativistic heavy-ion collisions. The coupling strength between the charm quarks and the QGP constituents, quantified by the spatial diffusion coefficient $2\pi TD_{s}$,…
A summary of measurements of the fragmentation of charm quarks into a specific hadron is given. Measurements performed in photoproduction and deep inelastic scattering in $e^{\pm}p$, $pp$ and $e^+e^-$ collisions are compared, using…