We report a direct lattice QCD calculation of the strange nucleon electromagnetic form factors GEs and GMs in the kinematic range 0≤Q21.2GeV2. For the first time, both GEs and GMs are shown to be nonzero with high significance. This work uses closer to physical lattice parameters than previous calculations, and achieves an unprecedented statistical precision by implementing a recently proposed variance reduction technique called hierarchical probing. We perform model-independent fits of the form factor shapes using the z-expansion and determine the strange electric and magnetic radii and magnetic moment. We compare our results to parity-violating electron-proton scattering data and to other theoretical studies.
|Original language||English (US)|
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|Publication status||Published - Aug 26 2015|
ASJC Scopus subject areas
- Nuclear and High Energy Physics