Related papers: Single Spin Asymmetries in Semi-Inclusive Electrop…
We study the single spin asymmetry (SSA) for the pion production in semi-inclusive deep inelastic scattering, $ep^\uparrow\to e\pi X$, in the framework of the collinear factorization. We derive the complete cross section formula associated…
We investigate the scaling properties in inclusive hadron production and the associated single transverse spin asymmetry in the forward rapidity region at RHIC. We find that the spin-averaged experimental data in both $pp$ and $dAu$…
We discuss the relevance of studying single transverse-spin asymmetry in hard-exclusive meson electroproduction in the backward region. Such an asymmetry could help us discriminate between contributions from a soft baryon exchange in the…
Some general remarks on parton transverse spin distributions and transverse motions are presented. The issue of accessing experimental information on the transversity distributions h_1^q is discussed. In particular direct information could…
A single-spin asymmetry in the distribution of exclusively produced pi^+ mesons azimuthally around the virtual photon direction relative to the lepton scattering plane has been measured for the first time in deep-inelastic scattering of…
We study the fragmentation of a transversely polarized quark into a non collinear (k_T not= 0) spinless hadron and the fragmentation of an unpolarized quark into a non collinear transversely polarized spin 1/2 baryon. These nonperturbative…
It is shown that the azimuthal dependence of the distribution of hadrons in a quark jet is a probe of the transverse spin of the quark initiating the jet. This results in a new spin-dependent fragmentation function that acts at the twist-2…
We study the semi-inclusive production of real, high-$p_T$, isolated photons in unpolarized and polarized lepton-proton collisions, $\ell p\to \ell\gamma X$. In particular we analyze the transverse nucleon single-spin asymmetry within the…
We study a possible origin of single spin asymmetries in the large $p_T$ inclusive production of hadrons in the scattering of unpolarized protons or leptons on transversely polarized nucleons. Such asymmetry is related to the single-spin…
A complete, fundamental understanding of the proton must include knowledge of the underlying spin structure. The transversity distribution, $h_1\left(x\right)$, which describes the transverse spin structure of quarks inside of a…
The perspectives of two new nonstandard methods of transversal quark polarization measurement are considered: the jet handedness and the so-called "Collins effect" due to spin dependent T-odd fragmentation function responsible for the…
We discuss polarized parton distributions and their effects on spin asymmetries at RHIC. In particular, transversity distributions and transverse spin asymmetry are studied. First, we show the $Q^2$ evolution difference between a…
We discuss the possibility of a direct access to transversity distributions by measuring the double transverse spin asymmetry A_TT in p pbar --> J/Psi + X --> l^- l^+ + X processes at future GSI-HESR experiments with polarized protons and…
The single-spin asymmetry of unpolarized leptons scattering deep-inelastically off transversely polarized nucleons is studied in a partonic picture within a collinear twist-3 framework. Since this observable is generated by multi-photon…
The investigation of transverse spin and transverse momentum effects in deep inelastic scattering is one of the key physics programs of the COMPASS collaboration. Three channels have been analyzed at COMPASS to access the transversity…
Recently HERMES has observed an azimuthal asymmetry in electro-production of neutral pions in semi-inclusive deep-inelastic scattering of unpolarized positrons off longitudinally polarized protons. This asymmetry (like those observed in the…
I review the most important single- and double-spin asymmetries that allow for the extraction of transversity and other chiral-odd and/or T-odd parton densities, necessary to explore the partonic content and the spin structure of the…
A short review of problems with parton distribution functions in nucleons, non-polarized and polarized, is given. The main part is devoted to the transversity distribution its possible measurement and its first experimental probe via spin…
By measuring transverse single spin asymmetries one has access to the transversity distribution function $\Delta_T q(x)$ and the transverse momentum dependent Sivers function $q_0^T(x,\vec{k}_T)$. New measurements from identified hadrons…
We explore the possibility of probing the nucleon's transversity distribution $\delta q(x)$ through the final state interaction between two mesons ($\pi^+\pi^-$, $\pi K$, or $K\bar K$) produced in transversely polarized nucleon-nucleon…