Related papers: Polarized Nucleon Structure Functions within a Chi…
Considering the nucleon as a system of confined valence quarks surrounded by pions we derive a Galster-like parameterization of the neutron electric form factor $G_E^n$. Furthermore, we show that the proposed parameterization can be linked…
We review the perturbative evolution of the polarized structure functions g_1 and their associated parton distribution functions, with particular emphasis on the anomalous coupling of the first moment of the polarized gluon distribution. We…
We analyse the available data on the polarized asymmetries $A_1$ for proton, neutron and deuteron targets. We use a homogeneous and updated set of unpolarized structure functions to derive $g_1$ from $A_1$, and we accurately correct for the…
In the present work we study the effect of the scalar spin coupling of constituent quarks on the nucleon electroweak properties by introducing a valence light-front wave function with two momentum scales. By comparing the results obtained…
Deep inelastic structure functions for the nucleon are obtained in a constituent quark model on the light cone. In the Bjorken limit the parton model is derived. Structure functions from the hadronic tensor at the scale $\mu \sim 0.25$ GeV…
We present a physical model for polarized and unpolarized structure functions and parton density functions (PDFs) of the proton and the neutron. It reproduces the data on F_2^p(x,Q^2) for 0.00001<x<1 and 2.5<Q^2<5000 GeV^2,…
We provide a consistent regularization procedure for calculating hadron structure functions in a chiral quark model. The structure functions are extracted from the absorptive part of the forward Compton amplitude in the Bjorken limit. Since…
The inclusive quasielastic response functions that appear in the scattering of polarized electrons from polarized nuclei are computed and analyzed for several closed-shell-minus-one nuclei with special attention paid to 39K. Results are…
Estimates for longitudinal spin asymmetries which single out new polarized nucleon structure functions in deeply inelastic charged current interactions at HERA energies are given, exploiting their interpretation in terms of polarized quark…
Modifications of baryon properties due to the restoration of the chiral symmetry in an external hot and dense baryon medium are investigated in an effective chiral quark-meson theory. The nucleon arises as a soliton of the Gell-Mann -…
After taking account of the scale dependence by means of the standard DGLAP evolution equation, the theoretical predictions of the chiral quark soliton model for the unpolarized and longitudinally polarized structure functions of the…
At large N_c the nucleon can be viewed as a soliton of the effective chiral lagrangian. This picture of nucleons allows a consistent nonperturbative calculation of the leading-twist parton distributions at a low normalization point. We…
Spin-polarizabilities are predicted by calculating the cross-section difference $\sigma_{3/2}-\sigma_{1/2}$ from available data for the resonance couplings $A_{3/2}$ and $A_{1/2}$ and CGLN amplitudes. The forward spin-polarizabilities are…
The nucleon spin structure is studied at COMPASS via the measurement of the spin dependent properties of deep inelastic muon-deuteron scattering. Both inclusive and semi-inclusive observables are investigated, with the emphasis put on the…
A phenomenological model for the nucleon structure functions is presented. Visualising the nucleon as a cavity filled with parton gas in equilibrium and parametrizing the effects due to the finiteness of the nucleon volume, we obtain a good…
We present the results of our final analysis of the full data set of g_1^p(Q^2), the spin structure function of the proton, collected using CLAS at Jefferson Lab in 2000-2001. Polarized electrons with energies of 1.6, 2.5, 4.2 and 5.7 GeV…
We performed a phenomenological fit in order to get quark parton polarized distributions in the nucleon. All data on inclusive and semi-inclusive spin asymmetries measured on nucleon targets were used. We present the results for the flavour…
Contents: 1. The sum rules or $\Gamma_{p,n}$.Theoretical status. 2. Calculations of matrix elements over the polarized nucleon by the QCD sum rule approach. 3. Twist-4 corrections to $\Gamma_{p,n}$ from QCD sum rules. 4. Gerasimov,…
We study the available data in polarized e-p deep inelastic scattering to test two different solutions to the so called spin crisis: one of them based on the axial gluon anomaly and consistent with the Bjorken sum rule and another one,…
Using the techniques of chiral effective field theories we evaluate the so called generalized polarizabilities of the nucleon, which characterize the structure dependent components in virtual Compton scattering (VCS) as probed in the…