Related papers: Spin Physics in the Resonance Region
First measurements of large Feynman x (x_F) neutral pion production in polarized proton collisions at sqrt(s)=200 GeV were reported previously. Cross section measurements at <eta>=3.3 and 3.8$ and analyzing power (A_N) measurements at…
Polarized proton-proton collisions at the Relativistic Heavy Ion Collider (RHIC) provide unique opportunities to study the spin structure of the nucleon. We will highlight recent results on the nucleon spin structure from the STAR and…
We explore the physics of the parton-hadron duality in the nucleon structure functions appearing in lepton-nucleon scattering. We stress that the duality allows one to extract the higher-twist matrix elements from data in the resonance…
Polarized antiprotons produced by spin filtering with an internal polarized gas target provide access to a wealth of single-- and double--spin observables, thereby opening a window to physics uniquely accessible with the HESR at FAIR. This…
In order to understand the gluon contribution to the nucleon spin, some experiments can study the production of hadrons at high transverse momemtum from lepton-nucleon or nucleon-nucleon scattering. RHIC has recently measured such double…
Single-spin asymmetries were investigated in inclusive electroproduction of charged pions and kaons from transversely polarized protons at the HERMES experiment. The asymmetries were studied as a function of the azimuthal angle $\psi$ about…
PROZA-M experiment results as well the proposal of a new spin program with the use of a polarized proton beam are presented. Significant asymmetries were observed in inclusive $\pi^0$ production. The new program proposes to study a wealth…
We report on recently published experimental results on spin sum rules, and particularly on the generalized spin polarizabilities $\gamma_0(Q^2)$ (for both the proton and neutron) and $\delta_\mathrm{LT}(Q^2)$ (for the neutron). The data…
The work presents the studies of the polarization observables in the single pion production (SPP) induced by the interaction of the muon neutrino (antineutrino) with nucleons. The SPP cross-sections and spin asymmetries are computed within…
Measurements of single-spin asymmetries for semi-inclusive electro-production of pions and kaons in deep-inelastic scattering with transverse target polarization open a new window on the transverse quark and gluon structure of the nucleon.…
We present new experimental results of the $^3$He spin structure function $g_2$ in the resonance region at $Q^2$ values between 1.2 and 3.0 (GeV/c)$^2$. Spin dependent moments of the neutron were then extracted. Our main result, the…
The Hermes experiment studies the spin structure of the nucleon using the 27.6 GeV longitudinally polarized positron beam of HERA and an internal target of pure gases. In addition to the well-known spin structure function g_1, measured…
New possibilities arising from the availability at GSI of antiproton beams, possibly polarised, are discussed. The investigation of the nucleon structure can be boosted by accessing in Drell-Yan processes experimental asymmetries related to…
In the near future, the Jefferson Lab $b_1$ experiment will provide the second measurement of tensor polarized asymmetries in inclusive DIS on the deuteron. In this asymmetry, 4 independent tensor polarized structure functions contribute.…
We present the recent JLab measurements on moments of spin structure functions at intermediate and low Q^2. The Bjorken sum and Burkhardt-Cottingham sum on the neutron are presented. The later appears to hold. Higher moments (generalized…
The possibility is investigated to measure the polarized structure function $g_1(x,Q^2)$ in the collider mode of HERA operating with a polarized lepton and proton beam. The $x$ dependence of $g_1$ can be measured at a statistical precision…
We calculate the spin dependent structure functions g_{1}(x) and g_{2}(x) of the proton and neutron. Our calculation uses the meson cloud model of nucleon structure, which has previously given a good description of the HERMES data on…
We report the first evidence for a non-zero beam-spin azimuthal asymmetry in the electroproduction of positive pions in the deep-inelastic region. Data have been obtained using a polarized electron beam of 4.3 GeV with the CLAS detector at…
We present a new measurement of the longitudinal spin asymmetry A_1^d and the spin-dependent structure function g_1^d of the deuteron in the range 1 GeV^2 < Q^2 < 100 GeV^2 and 0.004< x <0.7. The data were obtained by the COMPASS experiment…
Exclusive electroproduction of pi0 mesons on protons in the backward hemisphere has been studied at Q**2 = 1.0 GeV**2 by detecting protons in the forward direction in coincidence with scattered electrons from the 4 GeV electron beam in…