Related papers: Determining the Spin Structure of the Photon at Fu…
The new experimental measurements of beam spin asymmetry were performed for the deeply virtual exclusive $\pi^0$ production in a wide kinematic region with the photon virtualities $Q^2$ up to 8 GeV$^2$ and the Bjorken scaling variable $x_B$…
Beam polarisation is an integral part of the physics case of future Linear Colliders. In this contribution, important examples from Higgs coupling measurements, top and electroweak physics at high energies, the Z pole program as well as…
We propose to measure the linear polarization of the external electromagnetic fields of a relativistic heavy ion through azimuthal asymmetries in dilepton production in ultraperipheral collisions. The asymmetries estimated with the…
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.
Single-spin asymmetry appears due to the interference of single and double gluon exchange between protons. A heavy fermion model is used to describe the jet production in the interaction of gluon with the proton implying the further…
Spin-dependent quark densities, matrix elements of specific density operators in proton states of definite spin-polarization, indicate that the nucleon may harbor an infinite variety of non-spherical shapes. We show that these matrix…
Colliding beams of 70% polarized protons at up to $\sqrt{s}$=500 GeV, with high luminosity, L=2$\times10^{{\rm 32}}$ cm$^{-2}$sec$^{-1}$, will represent a new and unique laboratory for studying the proton. RHIC-Spin will be the first…
We report measurements of differential cross sections and decay asymmetries of incoherent $\phi$-meson photoproduction from the deuteron at forward angles using linearly polarized photons at \Eg=1.5-2.4 GeV. The nuclear transparency ratio…
We report measurements of the longitudinal double-spin asymmetry, $A_{LL}$, for inclusive jet and dijet production in polarized proton-proton collisions at midrapidity and center-of-mass energy $\sqrt{s}$ = 510 GeV, using the high…
A very promising spin physics programme will be soon on the way at the BNL Relativistic Heavy Ion Collider (RHIC). By studying the spin asymmetries for various processes (single photon, single-jet and $W^{\pm}$ production), we will compare…
There has been much recent research into possible methods of polarizing an antiproton beam, the most promising being spin filtering, the theoretical understanding of which is currently incomplete. The method of polarization buildup by spin…
Elastic lepton scattering off of a nucleon has proved to be an efficient tool to study the structure of the hadron. Modern cross section and asymmetry measurements at Jefferson Lab require effects beyond the leading order Born approximation…
We review how RHIC is expected to deepen our understanding of the spin structure of longitudinally polarized nucleons. After briefly outlining the current status of spin-dependent parton densities and pointing out open questions, we focus…
Physics perspectives are shown for future experiments in electron or positron scattering on nucleons, towards a deep and comprehensive understanding of the angular momentum structure of the nucleon in the context of Quantum Chromodynamics.…
Two kinds of asymmetry arise from the interference of the Born amplitude and the box-type amplitude corresponding to two virtual photons exchange, namely charge-odd and one spin asymmetries. In case of unpolarized particles the charge-odd…
A first measurement of beam spin asymmetries for $\pi^+\pi^0$ and $\pi^-\pi^0$ pairs in semi-inclusive deep inelastic scattering is reported. The asymmetries in the dihadron angular distributions were measured from the scattering of a 10.6…
The feasibility of an experimental determination of the parton distributions of virtual photons at high energy $ep$ colliders is studied in the context of the DESY-HERA collider. Recently proposed parton densities of virtual photons are…
Azimuthal asymmetry of vector-meson production in single-transversely polarized proton-proton collisions ($p\up p$) is calculated in the string model of particle production. The asymmetry is generated only during fragmentation of a…
There are four new structure functions for the spin-1 deuteron in comparison with the ones for the spin-1/2 proton, and they are called $b_1$, $b_2$, $b_3$, and $b_4$. The twist-2 structure functions $b_1$ and $b_2$ are expressed by…
Extensive experimental measurements of spin and azimuthal asymmetries in various processes have stimulated theoretical interest and progress in studies of the nucleon structure. Interpretation of experimental data in terms of parton…