We employ dimension-4 operators to improve the local vector and axial-vector currents and calculate the nucleon isovector axial coupling gA3 with overlap valence on 2+1-flavor domain wall fermion (DWF) sea. Using the equality of gA3 from the spatial and temporal components of the axial-vector current as a normalization condition, we find that gA3 is increased by a few percent towards the experimental value. The excited-state contamination has been taken into account with three time separations between the source and sink. The improved axial charges gA3(24I)=1.22(4)(3) and gA3(32I)=1.21(3)(3) are obtained on a 243×64 lattice at pion mass of 330 MeV and a 323×64 lattice at pion mass 300 MeV and are increased by 3.4% and 1.7% from their unimproved values, respectively. We have also used clover fermions on the same DWF configurations and find the same behavior for the local axial charge as that with overlap fermions.
|Journal||Physical Review D|
|State||Published - Aug 1 2017|
Bibliographical noteFunding Information:
We thank the RBC/UKQCD Collaborations for providing their DWF gauge configurations. This work is supported in part by the U.S. DOE Grant No. DE-SC0013065. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725. This work also used Stampede time under the Extreme Science and Engineering Discovery Environment (XSEDE)  , which is supported by National Science Foundation Grant No. ACI-1053575. We thank National Energy Research Scientific Computing Center (NERSC) for providing HPC resources that have contributed to the research results reported within this paper. We acknowledge the facilities of the USQCD Collaboration used for this research in part, which are funded by the Office of Science of the U.S. Department of Energy.
© 2017 American Physical Society.
ASJC Scopus subject areas
- Nuclear and High Energy Physics