Related papers: Applicability of Perturbative QCD to Pion Virtual …
We recalculated pion virtual Compton scattering in perturbative QCD in this paper. Our calculation avoids some deficiencies in existing literatures, and treats real Compton scattering as a limit case in which the mass of the virtual photon…
Pion Compton scattering is studied in perturbative QCD for real and space--like initial photons. Different methods for the convolution of the hard amplitude with the pion wave--functions, which have in the past led to conflicting results,…
In many years ago, Isgur and Llewellyn Smith addressed that PQCD is inapplicable to exclusive processes, such as the pion form factor.The main problem is that the asymptotic of PQCD is only about one fourth of the experimental value. We…
We compare two approaches to the description of pion Compton scattering at moderate momentum transfer, one being based on local duality QCD sum rules for the invariant amplitudes of the process, which have been derived recently, and the…
We present the results of calculations analyzing nucleon Compton scattering to lowest order using perturbative QCD (pQCD) methods. Two scenarios are considered: (1) the incoming photon is real; and (2) the incoming photon is virtual. The…
We investigate the transition to perturbative QCD in Compton processes, by concentrating on the specific reactions $\pi \gamma \to \pi \gamma$ and pion photoproduction at moderate energy scales. New sum rules for each of the helicities…
We show that the one-loop QCD correction to deeply-virtual Compton scattering can be factorized into the finite perturbative contributions and the collinearly-divergent terms, which correspond to the matrix elements of the off-forward…
A perturbative QCD treatment of the pion wave function is applied to computing the scattering amplitude for coherent high relative momentum di-jet production from a nucleon.
We study deeply virtual Compton scattering on a virtual pion that is emitted by a proton. Using a range of models for the generalized parton distributions of the pion, we evaluate the cross section, as well as the beam spin and beam charge…
We extend the analysis of the deeply virtual Compton scattering process to the weak interaction sector in the generalized Bjorken limit. The virtual Compton scattering amplitudes for the weak neutral and charged currents are calculated at…
We discuss possibilities of measurement of deeply virtual Compton scattering amplitudes via different asymmetries in order to access the underlying skewed parton distributions. Perturbative one-loop coefficient functions and two-loop…
At very high energy and wide angles, Compton scattering on the proton (gamma p -> gamma p) is described by perturbative QCD. The perturbative QCD calculation has been performed several times previously, at leading twist and at leading order…
We systematically evaluate observables for hard exclusive electroproduction of real photons and compare them to experiment using a set of Generalized Parton Distributions (GPDs) whose parameters are constrained by Deeply Virtual Meson…
We discuss a consistent treatment of the light-front gauge-boson and meson wave functions in the analyses of the generalized parton distributions(GPDs) and the scattering amplitudes in deeply virtual Compton scattering(DVCS) for the pion.…
We study perturbative QCD corrections to deeply virtual Compton scattering on an unpolarized nucleon target in the flavor non-singlet sector to next-to-next-to-leading order accuracy, restricting ourselves to the kinematically dominant…
Virtual Compton scattering off nucleons and pions at low energies is discussed. Predictions for the generalized polarizabilities of the nucleon are presented within the framework of heavy-baryon chiral perturbation theory and the linear…
Pion-loop corrections for Compton scattering are calculated in a novel approach based on the use of dispersion relations in a formalism obeying unitarity. The basic framework is presented, including an application to Compton scattering. In…
We extend QCD sum rule analysis to moderate energy fixed angle Compton scattering. In this kinematic region there is a strong similarity to the sum rule treatment of electromagnetic form factors, although the four-point amplitude requires a…
A selected set of topics along the borderline between perturbative and nonperturbative QCD in exclusive reactions are studied. Specific problems, related to different mechanisms of momentum transfer to an intact hadron, are discussed.…
Virtual Compton Scattering (VCS) at low transferred momenta to the proton ($t$) and sufficiently high c.m. energies ($s$) may be used to a) study $Q^2$--dependence of leading $t$--channel exchanges and b) look for onset of scaling behavior…