Related papers: Parametrising the proton structure function
I present a theoretical discussion of the uncertainties related to the QCD analysis of the proton structure function $F_2(x,Q^2)$ at small $x$. The role played by the `unphysical' gluon density is pointed out. It is shown how the study of…
We review recent developments in the theory and phenomenology of polarized structure functions. We summarize recent experimental data on the proton and deuteron structure function $g_1$, and their impact on the understanding of polarized…
We show how to consistently construct initial conditions for the QCD evolution equations for double parton distribution functions in the pure gluon case. We use to momentum sum rule for this purpose and a specific form of the known single…
The structure function $g_1(x,Q^2)$ is analysed within the formalism based on unintegrated spin dependent parton distributions incorporating the LO Altarelli-Parisi evolution and the double $ln^2(1/x)$ resummation at low $x$. We…
We explore several models of QCD evolution equations simplified by considering only the rapidity dependence of dipole scattering amplitudes, while provisionally neglecting their dependence on transverse coordinates. Our main focus is on the…
The use of the differential gluon structure function of the proton ${\cal F}(x,Q^{2})$ introduced by Fadin, Kuraev and Lipatov in 1975 is called upon in many applications of small-x QCD. We report here the first determination of ${\cal…
Q**2 dependence of nuclear structure functions is important for understanding perturbative QCD in nuclear environment. However, current experimental data are not sufficient for studying nuclear dependence in the Q**2 evolution because the…
I investigate the behavior of spin-dependent parton distribution functions in the regions of small and large momentum fractions $x$. I present a systematic comparison between predictions for relevant observables obtained with various models…
This talk reviews the latest measurements of the proton, Pomeron and photon structure functions. These measurements, especially at low $x$ and/or low $Q^2$ lead to new insight into the picture of hadronic interactions.
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…
QCD-inspired phenomenological analysis of experimental moments of proton and deuteron structure functions F2 have been presented. The obtained results on the d/u ratio at large-x, isospin dependence of higher twists and comparison with…
Approximate relations among transverse momentum dependent quark distribution functions are established in the framework of the QCD parton model. The validity of such results survives QCD evolution effects, owing to the Politzer theorem on…
A simple parametrisation of H1 and ZEUS data at HERA is given for the ranges in x and Q^2 of 10^{-4} - 5.10^{-2} and 5 - 250 GeV^2, respectively. This empirical expression is based on a strikingly similar dependence of the average charged…
We present exploratory studies of the proton structure via two distinct kinds of gluon densities: the transverse-momentum dependent functions, whose evolution is determined by the CSS equation, and the unintegrated gluon distribution, whose…
The QCD structure of the electron is defined and calculated. The leading order splitting functions are extracted, showing an important contribution from $\gamma$-$Z$ interference. Leading logarithmic QCD evolution equations are constructed…
We study the global Q^2 dependence of large x, F_2 nucleon structure function data, with the aim of providing a perturbative-QCD based, quantitative analysis of parton-hadron duality. As opposed to previous analyses at fixed x, we use a…
The $F_{2}$ structure functions of the inelastic lepton-hadron scattering is calculated in the case of non-zero intermediate gluon-quarks self-energy $M_{gq}^{2}$ and quasielastic limit. It is shown that in the quasielastic limit the…
We present a set of formulas to extract the longitudinal structure function from the proton structure function and its derivatives with respect to lnQ2 in the next-to-next-to-leading order of the perturbative theory at low x based on a hard…
A recently published soft Regge Dipole Pomeron model intended for all $x$ and $Q^2$ is proved to give a good agreement with (non fitted) recent HERA data from ZEUS (SVX95) on the protonstructure function $F_2^p(x,Q^2)$ at low $Q^2$ and low…
Hadron spin physics is now one of the most active fields of physics. Especially in the last ten years, great progress has been made both theoretically and experimentally that has considerably improved our knowledge of the spin structure of…