Related papers: Recent results on cold-QCD from RHIC
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…
We present a comprehensive phenomenological study of heavy flavor distributions and correlations in longitudinally polarized proton-proton collisions at BNL-RHIC. All results are obtained with a flexible parton-level Monte Carlo program at…
STAR collected data in proton-proton collisions at sqrt(s)=200 GeV with transverse and longitudinal beam polarizations during the 2003 running period at RHIC. We present preliminary results on single transverse spin asymmetries A_N in the…
We investigate the inclusive production of prompt J/psi mesons in polarized hadron-hadron and photon-hadron collisions in the factorization formalism of NRQCD. Numerical results are presented for BNL RHIC-Spin and the approved SLAC…
The physics programme for a possible fixed target polarized nucleon-nucleon collision experiment aiming at studying the nucleon spin structure at HERA is described. The experiment named HERA-N could be realized using an internal polarized…
We report a new high-precision measurement of the mid-rapidity inclusive jet longitudinal double-spin asymmetry, $A_{LL}$, in polarized $pp$ collisions at center-of-mass energy $\sqrt{s}=200$ GeV. The STAR data place stringent constraints…
The hot and dense matter formed in relativistic heavy-ion collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) is termed quark-gluon plasma (QGP). The evolution of the medium is characterized by non-trivial…
We propose a new measurement of the heavy flavor hadron double spin asymmetry in deep-inelastic scattering at a future Electron-Ion Collider (EIC) to constrain the polarized gluon distribution function inside the proton. Statistical…
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…
The double-helicity asymmetries ($A_{LL}$) of $\pi^{+}$ and $\pi^{-}$ production in polarized proton proton collisions are specially interesting probes of the gluon's polarization. Relative differences among $A_{LL}$ of positive, neutral,…
The PHENIX experiment at BNL-RHIC recently reported the single transverse spin asymmetry $A_N$ for forward neutrons measured in polarized proton-nucleus collisions at $\sqrt{s_{NN}} = 200\,$GeV; $A_N$ in proton-aluminum and proton-gold…
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…
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…
New results from polarized p-p collisions at sqrt(s)=200 GeV of double longitudinal spin asymmetry in pi0 production using the PHENIX detector in the 2005 RHIC run are presented. Both positive and negative maximal gluon polarization…
Strangeness measurement at RHIC energies constitutes one of the favorite theme of the STAR Collaboration. Besides the fact that strangeness enhancement has been proposed as a quark gluon plasma signature, its production provides various and…
The double longitudinal-spin asymmetry, $A_{LL}$, of the $J/\psi$ production in polarized proton-proton collisions is presented in this paper at QCD next-to-leading order. It is found that the obtained values of $A_{LL}$ are in general…
The inclusive A_1,p and hadron double-spin asymmetries A_p^pi+, A_p^pi-, A_p^K+, A_p^K- measured at COMPASS (CERN SPS) in deep-inelastic scattering of a polarized muon beam off a polarized NH_3 solid target are presented. The results have…
We study the single spin asymmetry in the back-to-back dijet production in transversely polarized proton-proton collisions. Such an asymmetry is generated by the Sivers functions in the incoming polarized proton. We propose a QCD formalism…
The study of two spin asymmetries in hadron-hadron collisions probes the details of fundamental particle interactions in ways infeasible to machines with unpolarized collisions. Within reach is how the proton spin is distributed among its…
We present preliminary results for the first measurements of the double longitudinal spin asymmetry A_LL in inclusive jet production at mid-rapidity in polarized proton-proton collisions at sqrt(s) = 200 GeV. The data amount to ~ 0.5 pb-1…