Related papers: Exploring the Spin Structure of the Nucleon at STA…
Since the announcement of the proton spin crisis by the European Muon Collaboration there has been considerable progress in unravelling the distribution of spin and orbital angular momentum within the proton. We review the current status of…
This is a review of what is currently known about the gluon Sivers distribution and of what are the opportunities to learn more about it. Because single transverse spin asymmetries in $p^\uparrow \, p \to \pi \, X$ provide only indirect…
Polarized electron-deuteron deep-inelastic scattering (DIS) with detection of the spectator proton ("tagged DIS") enables measurements of neutron spin structure with maximal control of nuclear effects. We calculate the longitudinal spin…
We have examined the spin structure of the proton in the region of the nucleon resonances (1.085 GeV < W < 1.910 GeV) at an average four momentum transfer of Q^2 = 1.3 GeV^2. Using the Jefferson Lab polarized electron beam, a spectrometer,…
The physics goals that will be addressed by colliding polarized protons at the Relativistic Heavy Ion Collider (RHIC) are described. The RHIC spin program provides a new generation of experiments that will unfold the quark, anti-quark and…
I review progress toward the experimental study of polarized proton collisions at RHIC, at center-of-mass energies of several hundred GeV. The tools under development for these experiments are summarized, with emphasis on the…
Measuring the spin structure of protons and neutrons tests our understanding of how they arise from quarks and gluons, the fundamental building blocks of nuclear matter. At long distances the coupling constant of the strong interaction…
The twenty years since the announcement of the proton spin crisis by the European Muon Collaboration has seen tremendous progress in our knowledge of the distribution of spin within the proton. The problem is reviewed, beginning with the…
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…
Plans are underway to measure spin asymmetries at large momentum transfer in hadron hadron collisions at RHIC and elsewhere. Proposals have focused on measuring quark transversity and quark and gluon helicity distributions in the nucleon.…
The Polarized Atomic Hydrogen Gas Jet Target polarimeter is employed by the Relativistic Heavy Ion Collider (RHIC) to measure the absolute polarization of each colliding proton beam. Polarimeter detectors and data acquisition were upgraded…
The helicity dependent parton distributions describe the number density of partons with given longitudinal momentum x and given polarization in a hadron polarized longitudinally with respect to its motion. After the discovery, more than 70…
In 2022, the COMPASS collaboration performed semi-inclusive measurements of deep-inelastic muon-scattering on a transversely polarised deuteron (6LiD) target. From these data, transverse-spin-dependent dihadron asymmetries are extracted…
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 have measured the spin-dependent structure function $g_1^p$ in inclusive deep-inelastic scattering of polarized muons off polarized protons, in the kinematic range $0.003 < x < 0.7$ and $1 GeV^2 < Q^2 < 60 GeV^2$. A next-to-leading order…
Investigating partonic interactions is one of the primary goals of the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC). RHIC is specially tailored for studying intrinsic partonic spin-momentum correlations due to its unique…
The STAR collaboration reported precision measurements on the transverse single spin asymmetries for the production of forward $\pi^0$ mesons from polarized proton collisions at $\sqrt{s}=$ 200 GeV. To disentangle contributions to measured…
The STAR Collaboration reports measurements of the transverse single-spin asymmetries, $A_N$, for inclusive jets and identified `hadrons within jets' production at midrapidity from transversely polarized $pp$ collisions at $\sqrt{s}$ = 200…
Measurements involving the gluon spin density, Delta G=G++ - G+-, can play an important role in the quantitative understanding of proton structure. To demonstrate this, we show that the shape of the gluon asymmetry, A(x,t)=Delta…
Recent progress from Jefferson Lab has significantly improved our understanding of the nucleon spin structure in the high-$x$ region. Results from two experiments in Hall A are presented. The first experiment is a precision measurement of…