2014/12/31 by Gunnar S. Bali, Gunnar Bali, Sara Collins +12 · 2 citations
Physics and Astronomy · #Diffraction #Excited state #High-Energy Particle Collisions Research #Isovector #Lattice (music) #Lattice QCD #Lattice constant #Lattice field theory #Meson #Nuclear physics #Nucleon #Particle physics #Particle physics theoretical and experimental studies #Physics #Pion #Pseudoscalar #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum mechanics #Quark #hep-lat
paper · pdf · doi:10.1103/physrevd.91.054501
22 pages, 31 Figures, v2: comparison with summation method added, minor typos corrected, legibility of figures improved, references added/updated
arxiv created 2015/02/27 · openalex publication_date 2015/03/05 · arxiv updated 2015/06/23 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We compute the axial, scalar, tensor and pseudoscalar isovector couplings of the nucleon as well as the induced tensor and pseudoscalar charges in lattice simulations with Nf=2 mass-degenerate nonperturbatively improved Wilson-Sheikholeslami-Wohlert fermions. The simulations are carried out down to a pion mass of 150 MeV and linear spatial lattice extents of up to 4.6 fm at three different lattice spacings ranging from approximately 0.08 fm to 0.06 fm. Possible excited state contamination is carefully investigated and finite volume effects are studied. The couplings, determined at these lattice spacings, are extrapolated to the physical pion mass. In this limit we find agreement with experimental results, where these exist, with the exception of the magnetic moment. A proper continuum limit could not be performed, due to our limited range of lattice constants, but no significant lattice spacing dependence is detected. Upper limits on discretization effects are estimated and these dominate the error budget.