Related papers: Photon Structure Functions: Target Photon Mass Eff…
Topological charge screening has been proposed as the mechanism responsible for the anomalous suppression in the first moment of the polarized proton structure function -- the `proton spin' effect. An immediate consequence is that this…
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…
We summarise the perturbative QCD analysis of the structure function data for g_1 from longitudinally polarized deep inelastic scattering from proton, deuteron and neutron targets, with particular emphasis on testing sum rules, determining…
The matrix element squared for Compton scattering of a heavy photon on a longitudinally polarized electron is calculated. The gauge-invariant tensor structure of the heavy photon polarization is considered, assuming that all kinematical…
The electroweak production processes of vector bosons, $e^+ e^- \rightarrow Z \gamma$, $\gamma e \rightarrow Ze$, and $\gamma e \rightarrow W \nu$ are considered simultaneousely and in the Standard model the covariant polarization density…
QCD corrections to the electron positron annihilation cross-section into hadrons and to the hadronic $Z$ boson decay rate are reviewed. Formal developments are introduced in a form particularly suited for practical applications. These…
The one-loop NLO radiative corrections to the observables in polarized DIS using assumption that a quark is an essential massive particle are considered. If compared with classical QCD formulae the obtained results are identical for the…
The polarization properties of perfectly periodical and defective one-dimensional photonic bandgap structures with nonreciprocal chiral (bi-isotropic) layers are studied. The method of solution is based on the 2x2-block-representation…
The electron, positron, and photon Parton Distribution Functions (PDFs) of the unpolarised electron have recently been computed at the next-to-leading logarithmic accuracy in QED, by adopting the $\overline{\rm MS}$ factorisation scheme. We…
We present an exploratory study of the electromagnetic corrections to meson masses and the hadronic vacuum polarization using $N_f=2+1$ Domain Wall fermions. These corrections are estimated with two different approaches, a stochastic…
The target mass effects in polarized DIS have been studied. It was demonstrated that taking into account the first order target mass corrections to g1 a very good approximation of the exact formula is achieved. It was also shown that their…
Several new developments in the calculation and interpretation of hadron density-density correlation functions are presented. The asymptotic behavior of correlation functions is determined from a tree diagram path integral. A method is…
For the magnetic field in order of the Schwinger critical value or much larger it, the effective mass of a real photon with a preset polarization is investigated in the energy region including two lower creation thresholds of electron and…
Motivated by experimental data at large momentum transfer we update the analysis of the two-photon exchange effect in the electron-nucleon scattering using the effective field theory formalism. Our approach is suitable for describing the…
Rather than regarding the restriction of current lattice QCD simulations to quark masses that are 5--10 times larger than those observed, we note that this presents a wonderful opportunity to deepen our understanding of QCD. Just as it has…
The main goals of `spin physics' are recalled, and some theoretical and phenomenological aspects of longitudinally polarized deep inelastic scattering and other hard processes are reviewed. The spin dependent parton densities of protons and…
Quark mass effects are clarified in the parton model approach to the transversely polarized nucleon structure function. The special propagator technique is employed to obtain manifestly gauge invariant results and extract the buried…
A review on the theoretical aspects and the experimental results of polarized deep inelastic scattering and of other hard scattering processes is presented. The following items are discussed: longitudinally polarized structure functions,…
In this thesis the polarized and unpolarized photon distributions of the nucleon (proton, neutron) $(\Delta)\gamma^N$, evaluated in the equivalent photon approximation (EPA), are computed theoretically and the possibility of their…
We have compared polarized parton densities determined in the NLO QCD fits to polarized structure functions and spin asymmetries. We consider models of such distributions based on MRST 99 and MRST 2001 fits to non-polarized data. Simple…