相关论文: Soft and hard QCD in charmonium production
Both hard and soft QCD dynamics are important in charmonium production, as presented here through a next-to-leading order QCD matrix element calculation combined with the colour evaporation model. Observed $x_F$ and $p_\perp$ distributions…
We show that both hard perturbative and soft non-perturbative QCD effects are important in hadroproduction of charmonium. Observed $x_F$ and $p_\perp$ distributions of J/psi in fixed target experiments can be well described by our Monte…
In the article, the study of unpolarized $J/\psi$ production in proton-proton collisions is presented. The Soft Gluon Resummation approach as a TMD framework was used for description of small-$p_T^{}$ production cross section. The Improved…
The direct charmonium and bottomonium production rate observed at high-pt in pp-bar collisions at the Tevatron is factors of ten larger than predictions based on conventional perturbative QCD. We show that this excess can be accounted for…
I discuss issues related to charmonium production, in view of physics possibilities at a 15 ... 30 GeV continuous beam electron facility. High energy photo- and hadroproduction of heavy quarkonia presents several challenges to QCD models…
Improved understanding of non-perturbative QCD dynamics can be obtained in terms of soft colour exchange models. Their essence is the variation of colour string-field topologies giving a unified description of final states in high energy…
The color evaporation model simply states that charmonium production is described by the same dynamics as $D \bar D$ production, {\em i.e.}, by the formation of a colored $c \bar c$ pair. Its color happens to be bleached by soft final-state…
We propose to investigate various charmonium states using their common decay channel to p pbar at LHC. Having the branching ratios for charmonium decaying into the p pbar final state measured or calculated, we propose to measure the…
Recent measurements of selected QCD processes at the Tevatron are reviewed and confronted with theoretical calculations. Results on inclusive jet production at large transverse momentum are compared to predictions from next-to-leading order…
Both hot QCD matter and extremely strong electromagnetic fields are generated in relativistic heavy-ion collisions. We employ the transport model and the equivalent photon approximation (EPA) to study charmonium hadroproduction and…
Soft quantum chromodynamics (QCD) measurements play an important role in fundamental QCD studies as well as in tuning of corresponding Monte Carlo generator models for a good description of experimental data. Recent results of soft QCD…
We firstly examine hadroproduction of prompt J/psi's at the Fermilab Tevatron in a Monte Carlo Framework by means of the event generator PYTHIA 5.7 in which those colour-octet matrix elements processes relevant for charmonium production…
Soft QCD is beyond perturbative control, and therefore phenomenological models have to be developed. These are implemented and combined within event generators. Typical aspects considered are multiparton interactions, colour reconnection,…
We investigate charmonium production in the hot medium created by heavy-ion collisions by setting up a framework in which in-medium charmonium properties are constrained by thermal lattice QCD (lQCD) and subsequently implemented into…
We study the charmonium coherent photoproduction and hadroproduction consistently with modifications from both cold and hot nuclear matters. The strong electromagnetic fields from fast moving nucleus interact with the other target nucleus,…
Programs that calculate observables in quantum chromodynamics at next-to-leading order typically generate events that consist of partons rather than hadrons -- and just a few partons at that. These programs would be much more useful if the…
We discuss two types of contributions to hadronic form factors in QCD: hard gluon exchange and soft wave function overlap. Within the QCD sum rule approach, the hard contribution has strong numeric suppression by factor (\alpha_s/\pi) ~ 0.1…
Nuclear suppression of charmonium production in proton-nucleus interactions is poorly understood, what restrains our attempts to single out unusual effects in heavy ion collisions. We develop a phenomenological approach, based on the…
QCD predicts soft radiation patterns that are particularly simple for $W+ {jet}$ production. We demonstrate how these patterns can be used to distinguish between the parton-level subprocesses probabilistically on an event-by-event basis. As…
Experimental studies of soft Quantum Chromodynamics (QCD) at Tevatron are reported in this note. Results on inclusive inelastic interactions, underlying events, double parton interaction and exclusive diffractive production and their…