6533b82bfe1ef96bd128cd9f

RESEARCH PRODUCT

Nucleon structure from Lattice QCD using a nearly physical pion mass

Jeremy GreenJeremy GreenSergey SyritsynSergey SyritsynMichael EngelhardtJohn W. NegeleStefan KriegStefan KriegAndrew Pochinsky

subject

QuarkNuclear and High Energy PhysicsParticle physicsNuclear TheoryHigh Energy Physics::LatticeNuclear TheoryLattice field theoryFOS: Physical sciencesLattice QCDNuclear Theory (nucl-th)Nucleon structureNuclear physicssymbols.namesakeHigh Energy Physics - LatticeHigh Energy Physics - Phenomenology (hep-ph)Pauli exclusion principlePionddc:530Nuclear ExperimentPhysicsQuantum chromodynamicsIsovectorHigh Energy Physics - Lattice (hep-lat)Form factorsLattice QCDHigh Energy Physics - PhenomenologysymbolsHigh Energy Physics::ExperimentNucleon

description

We report the first Lattice QCD calculation using the almost physical pion mass mpi=149 MeV that agrees with experiment for four fundamental isovector observables characterizing the gross structure of the nucleon: the Dirac and Pauli radii, the magnetic moment, and the quark momentum fraction. The key to this success is the combination of using a nearly physical pion mass and excluding the contributions of excited states. An analogous calculation of the nucleon axial charge governing beta decay has inconsistencies indicating a source of bias at low pion masses not present for the other observables and yields a result that disagrees with experiment.

yearjournalcountryeditionlanguage
2014-05-29Physics Letters B
https://doi.org/10.1016/j.physletb.2014.05.075