Related papers: Large $p_{\perp}$ Exclusive Processes:RECENT Devel…
I discuss the systematic modifications to the perturbative QCD factorization approach in high energy l+A, p+A and A+A reactions. These include transverse momentum diffusion manifest in the Cronin effect and a small increase in the dijet…
The Vector Pion form factor below 1 GeV is analyzed using experimental data on its modulus, the P-wave pion pion phase shifts and dispersion relation. It is found that causality is satisfied. Using dispersion relation, terms proportional to…
This Ph.D.~thesis is divided into two distinct parts. The first part focuses on hard exclusive scattering processes in Quantum Chromodynamics (QCD) at high energies, while the second part delves into spin phenomena at the Large Hadron…
We investigate the properties of interference fragmentation functions arising from the emission of two leading hadrons inside the same jet for inclusive lepton-nucleon deep-inelastic scattering. Using an extended spectator model for the…
Studying the instanton-induced contributions to various hard exclusive reactions provides physical insight into the transition from the non-perturbative to the perturbative regime of QCD. To this end, we study the leading-instanton…
This paper presents an extension of the MK single pion production model \cite{MK, MK2} to high hadron invariant mass ($W$) and high momentum transfer to conform to the predictions of perturbative QCD due to quark-hadron duality. New form…
Using deep inelastic scattering on a large nucleus as an example, we consider the transverse momentum broadening of partons in hard processes in the presence of medium. We find that one can factorize the vacuum radiation contribution and…
Experiments at CEBAF will scan the intermediate-energy region of the QCD dynamics for the nucleon form factors and for Compton Scattering. These experiments will definitely clarify the role of resummed perturbation theory and of…
Background: Measurements of forward exclusive meson production at different squared four-momenta of the exchanged virtual photon, $Q^2$, and at different four-momentum transfer, t, can be used to probe QCD's transition from meson-nucleon…
The pion cloud renormalises the light-cone wavefunction of the nucleon which is measured in hard, exclusive photon-nucleon reactions. We discuss the leading twist contributions to high-energy exclusive reactions taking into account both the…
The inclusive production of high-p_\perp particles (pions) in the beam fragmentation regions of high-energy hadronic collisions is driven by the breakup of valence constituents of the beam hadrons into their two-body Fock-state…
We study the impact of electroweak radiative corrections on direct production of photons with high transverse momenta at hadron colliders. Analytic results for the weak one-loop corrections to the parton scattering reaction $\bar q q \to…
We calculate the leading-order perturbative contribution to $\gamma p \to M_{V} p$, with $M_V$ being a $\Phi$ or $J/\Psi$ meson, in the kinematic region of large energy and scattering angle.
At the energies of present and future electron accelerators designed to study the structure of hadrons, there is a regime where hard pion electroproduction proceeds by a perturbatively calculable process in QCD. The process is not the…
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 exclusive processes $e^+e^-\to VP$, in the region of which the final state meson momentum is much larger than the hadronic scale $\Lambda_{QCD}$, are studied in the framework of PQCD approach based on the $k_T$ factorization. Including…
We summarize the results of a recent study of heavy quark production and attenuation in cold nuclear matter. In p+p collisions, we investigate the relative contribution of partonic sub-processes to $D$ meson production and $D$…
The pion-pole contribution to hadronic light-by-light scattering in the anomalous magnetic moment of the muon $(g-2)_\mu$ is fully determined by the doubly-virtual pion transition form factor. Although this crucial input quantity is, in…
We show that exclusive production of a pair of high transverse momentum photons in pion-nucleon collisions can be systematically studied in QCD factorization approach if the photon's transverse momentum $q_T$ with respect to the colliding…
In this review, we present and discuss the most recent results on inclusive and exclusive diffractive processes at HERA and Tevatron colliders. Measurements from fixed target experiments at HERMES and Jefferson laboratory are also reviewed.…