Flavor Structure of the Nucleon Sea from Lattice QCD
Journal
Physical Review
Journal Volume
D91
Pages
054510
Date Issued
2014-02
Author(s)
Abstract
We present the first direct lattice calculation of the isovector sea-quark distributions in the nucleon within the framework of the large-momentum effective field theory proposed recently. We use Nf=2+1+1 highly improved staggered quarks lattice gauge ensembles (generated by the MILC Collaboration) and clover valence fermions with pion mass 310 MeV. We establish the convergence of the result as the nucleon momentum increases within the uncertainty of the calculation. Although the lattice systematics are not yet fully under control, we obtain some qualitative features of the flavor structure of the nucleon sea: d¯(x)>u¯(x) leading to the violation of the Gottfried sum rule, Δu¯(x)>Δd¯(x) as indicated by the STAR data at large and small leptonic pseudorapidity.
SDGs
Type
journal article