Related papers: Analyzing the nucleon spin in weak interaction pro…
We have substantially extended our analysis of the partonic content of the pomeron. Ambiguities in the normalization of the pomeron flux and the possiblity of a direct coupling of the pomeron to single quarks are discussed, yielding two…
Several important and unique measurements, within the standard model and of possible physics beyond it, could be made with {\em polarized HERA} in which both the proton and the electron beams are polarized. With a $\sim$820 GeV proton beam…
We investigate the sea quark polarization in the nucleon by means of a combined next to leading order analysis to the recently enlarged set of inclusive and semi-inclusive polarized deep inelastic scattering data. Using the Lagrange…
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…
A Jefferson Lab experiment proposal was discussed in this talk. The experiment is designed to measure the beam-target double-spin asymmetries $A_{1n}^h$ in semi-inclusive deep-inelastic $\vec n({\vec e}, e^\prime \pi^+)X$ and $\vec n({\vec…
Double-spin asymmetries of semi-inclusive cross sections for the production of identified pions and kaons have been measured in deep-inelastic scattering of polarized positrons on a polarized deuterium target. Five helicity distributions…
The flavor dependence of polarized and unpolarized quark distributions in the nucleon can lead to insights into the formation of the sea. Drell-Yan measurements have pointed to flavor asymmetries in the unpolarized distributions. Collisions…
The discovery potential of the HERA collider, with and without polarized beams, for electron-quark contact interactions in neutral current scattering is reviewed. The measurement of spin asymmetries in the polarized case could give crucial…
The physics case for a possible fixed target polarized nucleon-nucleon collision experiment at HERA is described. The experiment named HERA-N could be realized using an internal polarized gas target in the HERA polarized/unpolarized proton…
We investigate the potential impact of forthcoming Jefferson Lab semi-inclusive polarized deep inelastic scattering proton measurements in the determination of the sea quark polarization in the nucleon by means of a next to leading order…
The data from the last seven experiments performed on polarized deep--inelastic scattering on proton and neutron (or deuteron) targets have been analyzed in search of a precise determination of the spin fraction carried by the quarks in the…
We explore the discovery and analysis potentials of the HERA collider, with and without polarized beams, in search for electron-quark contact interactions in the neutral current channel. We find that the sensitivity to contact interactions…
The physics of polarized nucleon--nucleon collisions originating from an internal polarized target in the HERA proton beam is investigated. Based on 240 pb^-1 integrated luminosity at 40 GeV c.m. energy, statistical sensitivities are given…
An earlier extraction from the HERMES experiment of the polarization-averaged parton distribution of strange quarks in the nucleon has been reevaluated using final data on the multiplicities of charged kaons in semi-inclusive deep-inelastic…
A multi-dimensional (x, y, z, P_{h\perp}) extraction of cos\phi_h and cos2\phi_h azimuthal asymmetries of unpolarized Semi-Inclusive Deep Inelastic Scattering at HERMES is discussed. The use of data taken with hydrogen and deuterium targets…
We study the Bjorken `x' (or equivalently Nachtmann `xi') dependence of the virtual photon spin asymmetry in polarized deep inelastic scattering of electrons from hadrons. We use an exactly solved relativistic potential model of the hadron,…
A summary is given of the experimental and theoretical results presented in the working group on spin physics. New data on inclusive and semi-inclusive deep-inelastic scattering, combined with theoretical studies of the polarized…
Spin properties of the nucleon are discussed based on the ongoing and planned measurements. Role, method and features of radiative corrections applied in the analyses are presented. Future prospects of the spin physics are reviewed.
Double-spin asymmetries for production of charged pions and kaons in semi-inclusive deep-inelastic muon scattering have been measured by the COMPASS experiment at CERN. The data, obtained by scattering a 160 GeV muon beam off a…
The spin physics parallel sessions at this workshop made a critical review of the physics potential of future experiments on polarized nucleons, with an emphasis on the potential impact of polarized electron-proton collisions at HERA. A…