Related papers: Distributions of N=1 QCD
We study the new relation [1] between the anomalous dimensions, resummed through next-to-next-to-leading-logarithmic order, in the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution equations for the first Mellin moments D_{q,g}(\mu^2) of…
We present a parametrization of the chiral even generalized parton distributions, $H$, $E$, $\widetilde{H}$, $\widetilde{E}$, for the quark, antiquark and gluon, in the perturbative QCD-parton framework. Parametric analytic forms are given…
Within QED, we examine several issues related to constructing a parton-model-based QCD transport theory. We rewrite the QED analog of the parton model, the Weizsaecker-Williams Approximation, entirely in terms of phase-space quantities and…
The task of Monte Carlo simulation of the evolution of the parton distributions in QCD and of constructing new parton shower Monte Carlo algorithms requires new way of organizing solutions of the QCD evolution equations, in which…
I review progress on selected issues connected with generalized parton distributions. Topics range from the description of hard exclusive reactions to the spatial distribution of quarks in the nucleon and the contribution of their orbital…
We present recent results on generalized parton distributions from dynamical lattice QCD calculations. Our set of twelve different combinations of couplings and quark masses allows for a preliminary study of the pion mass dependence of the…
A novel approach for describing the evolution of nucleon structure from the low-$Q^2$ regime to the high-$Q^2$ asymptotic region is proposed. This infrared-safe scheme modifies the parton distribution evolution equations to incorporate the…
Generalized parton distributions (GPDs) are studied at the hadronic (nonperturbative) scale within different assumptions based on a relativistic constituent quark model. In particular, by means of a meson-cloud model we investigate the role…
A method of obtaining parton distributions directly from data is revealed in this series. In the process, the first step would be developing appropriate matrix solutions of the evolution equations in $x$ space. A division into commuting and…
In this work, we investigate the constituent parton distribution functions (PDFs) of the kaon and heavy pseudoscalar mesons within the light-cone quark model. Starting from the initial scale quark and antiquark PDFs, obtained by evaluating…
We consider double parton distributions in the general case in which the virtualities of the interacting partons are different. We elaborate the corresponding evolution equations and their extension to next-to-leading logarithmic accuracy.
The $Q^2$ evolution of polarised parton fragmentation functions is discussed using Altarelli-Parisi evolution equations. The first moments of both polarised quark and gluon fragmentation functions are shown to behave in a similar fashion at…
The transversity generalized parton distributions (tGPDs) of the the pion, involving matrix elements of the tensor bilocal quark current, are analyzed in chiral quark models. We apply the nonlocal chiral models involving a…
We consider two simple covariant models for pions (one with scalar and the other with spin-1/2 constituents). Pion generalized parton distributions are derived by integration over the light-cone energy. The model distributions are…
New type of parametrization for parton distribution functions, based on an exact their Q^2-evolution at large and small x values, is constructed for valence quarks. It preserves exactly the low x and large x asymptotics of the solution of…
We study the one dimensional partially asymmetric simple exclusion process (ASEP) with open boundaries, that describes a system of hard-core particles hopping stochastically on a chain coupled to reservoirs at both ends. Derrida, Evans,…
We have used QCD and polarized deep-inelastic scattering data to construct x-dependent polarized parton distributions. These flavor dependent distributions evolve under the NLO DGLAP equations, satisfy positivity constraints and agree well…
Quark and gluon helicity flip generalized parton distributions (GPDs) encode the information on the nucleon structure in the transversity sector. In order to build a theoretically consistent phenomenological parametrization for these…
We studied the effects of NLO $Q^2$ evolution of generalized parton distributions (GPDs) using the aligned-jet model for the singlet quark and gluon GPDs at an initial evolution scale. We found that the skewness ratio for quarks is a slow…
We construct off-diagonal parton distributions defined on the interval 0 < X < 1 starting from the off-forward distributions defined by Ji. We emphasize the particular role played by the symmetry relations in the "ERBL-like" region. We find…