2011/12/31 by Gunnar S. Bali, Gunnar Bali, Sara Collins +15 · 96 citations
Physics and Astronomy · #Baryon #Extrapolation #High-Energy Particle Collisions Research #Lattice (music) #Lattice QCD #Nuclear physics #Nucleon #Particle physics #Particle physics theoretical and experimental studies #Physics #Pion #Proton #Proton spin crisis #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quark #Strangeness #hep-lat #hep-ph
paper · pdf · doi:10.1103/physrevlett.108.222001
published in Physical Review Letters 108(22), 222001 (American Physical Society) · 5 pages, 2 figures, V2: minor changes, to enhance the readability of the article. References updated. "The" removed from the title
arxiv created 2012/05/18 · openalex publication_date 2012/05/30 · arxiv updated 2012/06/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We compute the strangeness and light-quark contributions \ensuremathΔs, \ensuremathΔu, and \ensuremathΔd to the proton spin in nf=2 lattice QCD at a pion mass of about 285 MeV and at a lattice spacing a\ensuremath≈0.073 fm, using the nonperturbatively improved Sheikholeslami-Wohlert Wilson action. We carry out the renormalization of these matrix elements, which involves mixing between contributions from different quark flavors. Our main result is the small negative value \ensuremathΔs^MS(√(7.4) GeV)=\ensuremath-0.020(10)(4) of the strangeness contribution to the nucleon spin. The second error is an estimate of the uncertainty, due to the missing extrapolation to the physical point.