Abstract
We present a calculation of the strange and charm quark contributions to the nucleon spin from the anomalous Ward identity (AWI). This is performed with overlap valence quarks on 2+1-flavor domain-wall fermion gauge configurations on a 243×64 lattice with lattice spacing a-1=1.73 GeV and the light sea mass at mπ=330 MeV. To satisfy the AWI, the overlap fermion for the pseudoscalar density and the overlap Dirac operator for the topological density, which do not have multiplicative renormalization, are used to normalize the form factor of the local axial-vector current at finite q2. For the charm quark, we find that the negative pseudoscalar term almost cancels the positive topological term. For the strange quark, the pseudoscalar term is less negative than that of the charm. By imposing the AWI, the strange gA(q2) at q2=0 is obtained by a global fit of the pseudoscalar and the topological form factors, together with gA(q2) and the induced pseudoscalar form factor hA(q2) at finite q2. The chiral extrapolation to the physical pION mass gives Δs+Δs=-0.0403(44)(78).
| Original language | English |
|---|---|
| Article number | 114509 |
| Journal | Physical Review D |
| Volume | 95 |
| Issue number | 11 |
| DOIs | |
| State | Published - Jun 1 2017 |
Bibliographical note
Publisher Copyright:© 2017 American Physical Society.
Funding
This work is supported in part by the National Science Foundation of China (NSFC) under Project No. 11405178, the Youth Innovation Promotion Association of CAS (2015013), and the U.S. DOE Grant No. DE-SC0013065. A.A. is supported in part by the National Science Foundation CAREER Grant No. PHY-1151648 and by U.S. DOE Grant No. DE-FG02-95ER40907. 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 the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation Grant No. ACI-1053575.
| Funders | Funder number |
|---|---|
| National Science Foundation Office of International Science and Engineering | |
| U.S. Department of Energy Oak Ridge National Laboratory U.S. Department of Energy National Science Foundation National Energy Research Scientific Computing Center | DE-AC05-00OR22725, DE-SC0013065, ACI-1053575 |
| U.S. Department of Energy Chinese Academy of Sciences Guangzhou Municipal Science and Technology Project Oak Ridge National Laboratory Extreme Science and Engineering Discovery Environment National Science Foundation National Energy Research Scientific Computing Center National Natural Science Foundation of China | DE-FG02-95ER40907, 1151648 |
| Youth Innovation Promotion Association of the Chinese Academy of Sciences | 2015013 |
| National Natural Science Foundation of China (NSFC) | 11405178 |
ASJC Scopus subject areas
- Nuclear and High Energy Physics