相关论文: Diffractive electroproduction of two mesons separa…
We calculate at the leading order in $\alpha_s$ the QCD amplitude for exclusive neutrino production of a $D^*$ or $D_s^*$ charmed vector meson on a nucleon. We work in the framework of the collinear QCD approach where generalized parton…
We consider pion pair production in two-photon collisions, gamma* gamma -> pi+ pi-, at large photon virtuality Q^2 and center-of-mass energy \sqrt{s} in the hard-scattering picture. In the limit where s is large but s << Q^2 we derive an…
Diffractive scattering involves exchange of a Pomeron to make a rapidity gap. It is normally assumed that to get a hard scattering in diffraction, one may treat the Pomeron as an ordinary particle, which has distributions of gluons and…
We utilize non-perturbative and fully relativistic methods to calculate the\thinspace \thinspace $\Delta N\gamma $ electromagnetic transition amplitudes $G_{M}^{*}(q^{2})$ (related to the magnetic dipole moment $% M_{1^{+}}^{3/2}(q^{2})$),…
Very recently, a lattice QCD collaboration has explored threshold pion electroproduction near the physical pion mass and has simulated the relevant multipole amplitudes. Different multipole amplitudes are usually entangled in experimental…
We calculate the leading order in $\alpha_s$ QCD amplitude for exclusive neutrino and antineutrino production of a $D$ pseudoscalar charmed meson on an unpolarized nucleon. We work in the framework of the collinear QCD approach where…
Within the kt-factorization approach, we evaluate the impact factor of the transition gamma* -> rhoT taking into account the twist 3 contributions. We show that a gauge invariant expression is obtained with the help of QCD equations of…
Hard diffractive electroproduction of longitudinally polarized vector mesons is calculated within the leading $\alpha_s\ln{Q^2\over\Lambda_{QCD}^2}$ approximation of QCD using the leading order parton densities within the nucleon. Novel QCD…
Parton evolution with the rapidity essentially is a branching diffusion process. We describe the fluctuations of the density of partons which affect the properties of QCD scattering amplitudes at moderately high energies. We arrive at…
We use perturbative QCD and parton-hadron duality to estimate the cross sections for the diffractive electroproduction of rhoprime(1-) and rho(3-) resonances which occur in the 1.3-1.8 GeV mass interval. We present the cross sections and…
The study of those rapidity gap processes where a large momentum is transferred across the rapidity gap provides an ideal opportunity to understand the gap producing mechanism wholly within the framework of QCD perturbation theory. The…
We calculate the cross-section for the diffractive exclusive process gamma*_L (Q_1^2) gamma*_L(Q_2^2) -> rho^0_L rho^0_L, in view of its study in the future high energy e+e- linear collider. The Born order approximation of the amplitude is…
In the large $N_c$ approximation to $QCD$, the leading $\pp$ scattering amplitude is expressed as the sum of an infinite number of tree diagrams. We investigate the possibility that an adequate approximation at energies up to somewhat more…
We perform a QCD analysis of the exclusive production of two mesons in gamma^* gamma collisions in the kinematical domain of large photon virtuality Q and small hadronic invariant mass W. This reaction is dominated by a scale invariant…
We present a nonperturbative QCD calculation of diffractive vector meson production in virtual photon nucleon scattering at high energy. We use the nonperturbative model of the stochastic QCD vacuum which yields linear confinement and makes…
Dijet production with a rapidity gap between the jets is considered as a test ground for the production of a heavy Higgs boson via weak-boson fusion at hadron supercolliders. It is argued that in order to perform a detailed analysis of…
The cross section for coherent nuclear processes in which an incident meson or photon dissociates diffractively into two jets of high relative transverse momentum (between about 1 and 3 GeV/c) is found to be proportional in QCD to $A^2$ in…
We analyze the available data on eta photo- and electroproduction, around W~1535 MeV, in the framework of the effective Lagrangian approach, and extract, in a nearly model-independent fashion, the electrostrong amplitude for the gamma+N-->…
The overlap representation of skewed parton distributions is discussed and applications to wide-angle Compton scattering and electroproduction of mesons are presented. The amplitudes for these processes factorise into parton-level…
Starting with the interpretation of parton evolution with rapidity as a branching-diffusion process, we describe the different kinds of fluctuations of the density of partons which affect the properties of QCD scattering amplitudes at…