Related papers: Large-distance effects on spin observables at RHIC
In non-central high energy heavy ion collisions, the colliding system possesses a huge orbital angular momentum along the normal direction of the reaction plane. Due to the spin orbit interaction in the system, such a huge orbital angular…
We re-examine the extraction of \rho(s,t), the ratio of the real part to the imaginary part of the scattering amplitude, and of the spin-flip amplitude, from the existing experimental data in the Coulomb-hadron interference region. We show…
The pp polarization data confirm the presence of a diffractive-like (Pomeron) contribution in the spin-flip amplitude. The extrapolation to RHIC energies does not appear very promising.
We report on the first measurement of the single spin analyzing power ($A\_N$) at $\sqrt{s}=200$ GeV, obtained by the pp2pp experiment using polarized proton beams at the Relativistic Heavy Ion Collider (RHIC). Data points were measured in…
We analyze the electromagnetic scattering of massive particles with and without spin and, using the techniques of effective field theory, we isolate the leading long distance effects beyond one photon exchange, both classical and quantum…
Significant differences between transverse and longitudinal polarized parton distributions are found at low energies within a light-front covariant quark model of the nucleon. These differences are due to relativistic spin effects…
We show that, to a very good approximation, the ratio of the spin-flip to the non-flip parts of the elastic proton-nucleus amplitude is the same as for proton-nucleon scattering at very high energy. The result is used to do a realistic…
Recent highlights from the spin program at the Relativistic Heavy Ion Collider (RHIC), focusing on the gluon contribution to the proton spin and the polarization of the light flavor sea, are presented. The impact of these data on recent…
The impact-parameter representation of the spin-flip amplitude of hadron elastic scattering is examined in different unitarisation schemes, taking the Born term of the spin-flip amplitude from the Dubna Dynamical Model (DDM). It is shown…
In the framework of the model, where the scattering amplitude is determined by the first and second moments of the GPDs, the qualitative description of all existing experimental data at $\sqrt{s} \geq 52.8 $ GeV, including the Coulomb range…
The high energy part of the hadron spin flip amplitude is examined in the framework of the new high energy general structure (HEGS) model of the elastic hadron scattering at high energies. The different forms of the hadron spin flip…
Coulomb-nuclear interference in the single transverse spin asymmetry A_N is often considered as a possible absolute polarimeter for proton beams. The main uncertainty in this is the unknown hadronic spin-flip amplitude. This uncertainty is…
Time and again, spin has been a key element in the exploration of fundamental physics. Spin-dependent observables have often revealed deficits in the assumed theoretical framework and have led to novel developments and concepts. Spin is…
Large-distance effects, which lead to the spin-flip part of the hadron -pomeron coupling in QCD -models, are discussed. We study spin asymmetries in exclusive reactions and in diffractive $Q \bar Q$ and vector meson production which are…
Spin transport properties of a spin-polarized two-dimensional electron gas are studied in the presence of electron-electron interactions. Longitudinal and transverse spin diffusion coefficients are calculated with the quantum transport…
Some nonperturbative aspects of spin studies at RHIC are discussed and the predictions for single- and two-spin asymmetries are given. Among them are those which emphasize the role of angular orbital momentum in the spin structure of the…
The study of slope parameter is presented for elastic proton-proton and antiproton-proton scattering with taking into account the resent experimental data at high energies. The expanded logarithmic approximations allow the description of…
There is no theoretical reason to think that the spin-flip component of the Pomeron is zero. One can measure the spin-flip part using Coulomb-nuclear interference (CNI). Perturbative QCD calculations show that the spin-flip component is…
The longitudinal double spin asymmetry A_LL in the reaction pp --> pi X has been measured at RHIC with extremely interesting consequences. If the gluon polarization in a proton were as big as needed to resolve the famous "spin crisis" then…
In non-central high energy heavy ion collisions the colliding system posses a huge orbital angular momentum in the direction opposite to the normal of the reaction plane. Due to the spin-orbit coupling in strong interaction, such huge…