2014/04/30 by STAR Collaboration, L. Adamczyk, J. K. Adkins +368 · 3 citations
Physics and Astronomy · #Asymmetry #Boson #Charged particle #Deep inelastic scattering #Electron #High-Energy Particle Collisions Research #Inelastic scattering #Lepton #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Polarization (electrochemistry) #Proton #Pseudorapidity #Quantum Chromodynamics and Particle Interactions #Quark #Range (aeronautics) #Scattering #Spin (aerodynamics) #hep-ex #nucl-ex
paper · pdf · doi:10.1103/physrevlett.113.072301
published as Phys. Rev. Lett. 113, 072301 (2014) · 7 pages, 5 figures, Submitted to Physical Review Letters; replaced with published version
arxiv created 2014/08/12 · openalex publication_date 2014/08/13 · arxiv updated 2014/08/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
We report measurements of single- and double-spin asymmetries for W± and Z/γ* boson production in longitudinally polarized p+p collisions at sqrt[s]=510 GeV by the STAR experiment at RHIC. The asymmetries for W± were measured as a function of the decay lepton pseudorapidity, which provides a theoretically clean probe of the proton's polarized quark distributions at the scale of the W mass. The results are compared to theoretical predictions, constrained by polarized deep inelastic scattering measurements, and show a preference for a sizable, positive up antiquark polarization in the range 0.05<x<0.2.