Related papers: NLO Oriented Event-Shape Distributions for Massive…
We discuss the Wigner functions of the nucleon which provide multi-dimensional images of the quark distributions in phase space. They combine in a single picture all the information contained in the generalized parton distributions (GPDs)…
Fragmentation of heavy quarks into heavy-flavoured hadrons receives both perturbative and non-perturbative contributions. We consider perturbative QCD corrections to heavy quark production in $e^+e^-$ collisions to next-to-next-to-leading…
We present precision results for distributions in global event shapes that can be measured at hadron colliders within experimental limitations. These predictions are obtained by combining exact next-to-leading order (NLO) with the all-order…
We study power corrections to the event shapes in $\e^+\e^--$annihilation in the two jets kinematical region, $e\ll 1$. We argue that for $e \sim \Lambda_{QCD}/Q$ all power corrections of the form $1/\lr{Qe}^n$ have to be taken into account…
We argue that due to Parity constraints, the helicity combination of the purely momentum space counterparts of the Wigner distributions -- the generalized transverse momentum distributions -- that describes the configuration of an…
We study the off-forward quark distributions (OFQD's) in the chiral quark-soliton model of the nucleon. This model is based on the large-N_c picture of the nucleon as a soliton of the effective chiral lagrangian and allows to calculate the…
We describe predictions for top-quark pair differential distributions at hadron colliders, which combine state-of-the-art NNLO QCD calculations and NLO electroweak corrections together with double resummation at NNLL$'$ accuracy of…
This is a doctoral thesis dissertation developed in the frame of theoretical QCD predictions, with focus on two main topics. On the one hand, the large-order bahavior of perturbative QCD series is discussed. By reviewing the main…
Semiclassical catastrophes in the dynamics of a quantum rotor (molecule) driven by a strong time-varying field are considered. We show that for strong enough fields, a sharp peak in the rotor angular distribution can be achieved via…
In the Quantum Electrodynamics process $e^{+}e^{-}\to l^{+}l^{-}(n\gamma)$, there are two well known angular asymmetries in the $cos(\theta)$ and the $cos(\theta^{*})$ distributions. In this paper, the QED angular asymmetry related to the…
We compute the two-loop heavy quark jet-function in the heavy quark limit. This is one of the key ingredients in next-to-next-to-leading order (NNLO) and next-to-next-to-leading-log order (NNLL) computations of the invariant mass…
The earlier introduced method of calculation of quark distributions in hadrons, based on QCD sum rules, is improved. The imaginary part of the virtual photon forward scattering amplitude on some hadronic current is considered in the case,…
We discuss electromagnetic currents in the point-form formulation of relativistic quantum mechanics. The construction is along a spectator model and implies that only one quark is explicitly coupled to the photon, but nevertheless many-body…
Event shape observables have been widely used for precision QCD studies at various lepton and hadron colliders. We present the most accurate calculation of the transverse-energy-energy correlation event shape variable in deep-inelastic…
This paper presents a comprehensive study of top quark phenomenology within the Non-Commutative Standard Model. We calculate non-commutative corrections to the squared amplitudes for top quark pair production, as well as for single top…
A group theoretical procedure for parametrizing non-forward matrix elements of non-local QCD operators is introduced. The related (two-variable) distribution amplitudes are given as sum over power corrections of the double distributions.…
We present the O(alpha_s) corrections to the cross section for the reaction e+e- --> gamma^* --> Q \bar Q in the energy region close to the threshold. We assume that the energy of the reaction is such that both the perturbative expansion in…
We use the next-to-next-to-leading order (NNLO) contributions to anomalous dimension governing the evolution of non-singlet quark distributions. We use the xF3 data of the CCFR collaboration to obtain some unknown parameters which exist in…
Data from e+e- annihilation into hadrons collected by the JADE experiment at centre-of-mass energies between 14 GeV and 44 GeV were used to study moments of event shape distributions. The data were compared with Monte Carlo models and with…
We revisit the calculation of perturbative quark transverse momentum dependent parton distribution functions and fragmentation functions using the exponential regulator for rapidity divergences. We show that the exponential regulator…