相关论文: Dispersion relations and QCD factorization in hard…
In this work we estimate the differential cross section for the high energy deeply virtual Compton scattering on a photon target within the QCD dipole-dipole scattering formalism. For the phenomenology, a saturation model for the…
I review the basics of the collinear factorization theorem applied primarily to deep inelastic scattering (DIS) involving forward parton distributions (PDFs) and the extensions of this theorem for exclusive processes probing non-forward…
The process of exclusive heavy vector meson photoproduction, gamma p -> V p, is studied in the framework of QCD factorization. The mass of the produced meson, V = Upsilon or J/Psi, provides a hard scale for the process. We demonstrate, that…
Exclusive electro-weak processes have peculiar features which make them complementary to usually discussed deeply virtual electroproduction processes such as deep virtual Compton scattering or meson production (and the corresponding crossed…
I show that factorization for hard processes in QCD is also valid when the detected particles are polarized, and that the proof of the theorem determines the operator form for the parton densities. Particular attention is given to the case…
In this contribution we analyse the cross sections for the exclusive vector meson production as well as the deeply virtual Compton scattering (DVCS) relying on the color dipole approach and considering the numerical solution of the…
Exclusive and semi-exclusive processes, the diffractive dissociation of hadrons into jets, and hard diffractive processes such as vector meson leptoproduction provide new testing grounds for QCD and essential information on the structure of…
Recent experimental results on inclusive diffractive scattering and on exclusive vector meson production are reviewed. The dynamical picture of hard diffraction emerging in perturbative QCD is highlighted.
Applications of perturbative QCD to deeply virtual Compton scattering and hard exclusive electroproduction processes require a generalization of usual parton distributions for the case when long-distance information is accumulated in…
We prove $k_T$ factorization theorem in perturbative QCD (PQCD) for exclusive processes by considering $\pi\gamma^*\to \gamma(\pi)$ and $B\to\gamma(\pi) l\bar\nu$. The relevant form factors are expressed as the convolution of hard…
Exclusive two-photon reactions such as Compton scattering at large angles, deeply virtual Compton scattering, and hadron production in photon-photon collisions provide important tests of QCD at the amplitude level, particularly as measures…
Photoproduction of a pair of particles with large invariant mass is a natural extension of collinear QCD factorization theorems which have been much studied for deeply virtual Compton scattering and deeply virtual meson production. We…
We show that factorization holds for the deeply virtual Compton scattering amplitude in QCD, up to power suppressed terms, to all orders in perturbation theory. Furthermore, we show that the virtuality of the produced photon does not…
We outline $QCD$ predictions for the diffractive electroproduction of heavy flavor vector mesons and compare them with available data.
Following recent predictions that the geometric scaling properties of deep inelastic scattering data in inclusive gamma*-p collisions are expected also in exclusive diffractive processes, we investigate the diffractive production of vector…
The existing theory of hard exclusive QCD processes is based on two assumptions: (i) $factorization$ into a $hard\,block$ times light front distribution amplitudes (DA's); (ii) use of perturbative gluon exchanges within the hard block.…
This talk summarized the proof of hard-scattering factorization for exclusive deep-inelastic processes, such as diffractive meson production.
Several hard exclusive scattering processes admit a description in terms of generalized parton distributions and perturbative hard-scattering kernels. Both the physical amplitude and the hard-scattering kernels fulfill dispersion relations.…
I discuss recent progress in the theory of exclusive meson production and Compton scattering, focusing on hard-scattering factorization and on the dipole formalism.
We consider the factorization properties of on-shell QCD amplitudes with massive partons in the limit when all kinematical invariants are large compared to the parton mass and discuss the structure of their infrared singularities. The…