Related papers: Quark Distribution Functions in a Diquark Spectato…
Starting from Martin, Roberts and Stirling fit for unpolarized deep inelastic structure functions and using the newest experimental data on spin asymmetries we get a fit which provides polarized quark distributions. We analyze the behaviour…
Self- and cross-diffusion are important nonlinear spatial derivative terms that are included into biological models of predator-prey interactions. Self-diffusion models overcrowding effects, while cross-diffusion incorporates the response…
We construct a model for inelastic neutrino- and electron-nucleon scattering cross sections using effective leading order parton distribution functions with a new scaling variable $\xi_w$. Non-perturbative effects are well described using…
We present first results from a simulation of quenched overlap fermions with improved gauge field action. Among the quantities we study are the spectral properties of the overlap operator, the chiral condensate and topological charge, quark…
The pion structure function is investigated in a simple model, where the pion and its constituent quark fields are coupled through the simplest pseudoscalar coupling. The imaginary part of the forward gamma* pi -> gamma* pi scattering…
A large class of polarized and unpolarized deep inelastic data is successfully described with Fermi-Dirac functions for the non-diffractive part of quark parton distributions. The NLO approach used here improves the agreement with…
The nucleon axial vector form factor is investigated in a light-cone quark spectator diquark model, in which Melosh rotations are applied to both the quark and vector diquark. It is found that this model gives a very good description of…
A behavior of the nucleon structure functions in the resonance region is investigated. Expressions for resonance production form factors, dependent on photon virtuality $Q^2$, which have correct threshold behavior and take into account…
When more than one hadron takes part in a hard process, an extended set of quark distribution and fragmentation functions becomes relevant. In this talk, the derivation of Soffer-like bounds for these functions, in the case of a spin-1/2…
Generalized parton distributions have been introduced in recent years as a suitable theoretical tool to study the structure of the nucleon. Unifying the concepts of parton distributions and hadronic form factors, they provide a…
We use local quark-hadron duality to calculate the nucleon structure function as seen by neutrino and muon beams. Our result indicates a possible signal of charge symmetry violation at the parton level in the very large x region.
We apply chiral quark model with momentum dependent quark mass to two kinds of non-perturbative objects. These are: photon Distribution Amplitudes which we calculate up to twist-4 in tensor, vector and axial channels and pion-photon…
We present a calculation of the perturbative quark-to-quark transverse parton distribution function at next-to-next-to-leading order based on a gauge invariant operator definition. We demonstrate for the first time that such a definition…
Quantum phase-space distributions (Wigner functions) for the plane rotator are defined using wave functions expressed in both angle and angular momentum representations, with emphasis on the quantum superposition between the Fourier dual…
Distribution functions in hard processes can be described by quark-quark correlators, nonlocal matrix elements of quark fields. Color gauge invariance requires inclusion of appropriate gauge links in these correlators. For transverse…
We discuss the recent interpretation of quark distribution functions in the plane transverse to the light-cone direction. Such a mapping is model independent and allows one to build multidimensional pictures of the hadron and to develop a…
Determination of parton distribution functions in nuclei is important for calculating nuclear corrections in oscillation experiments, from which detailed information should be extracted on neutrino properties. First, nuclear parton…
It has been recognized recently that fractional calculus is useful for handling scaling structures and processes. We begin this survey by pointing out the relevance of the subject to physical situations. Then the essential definitions and…
Dyson-Schwinger equation treatments of the strong interaction show that the presence and importance of nonpointlike diquark correlations within the nucleon are a natural consequence of dynamical chiral symmetry breaking. Using this…
We study the problem of designing distributed functional observers for LTI systems. Specifically, we consider a setting consisting of a state vector that evolves over time according to a dynamical process. A set of nodes distributed over a…