Extracting nucleon strange and anapole form factors from world data

Abstract

The complete world set of parity-violating electron scattering data up to Q²∼0.3 GeV² is analyzed. We extract the current experimental determination of the strange electric and magnetic form factors of the proton, as well as the weak axial form factors of the proton and neutron, at Q²=0.1 GeV². Within experimental uncertainties, we find that the strange form factors are consistent with zero, as are the anapole contributions to the axial form factors. Nevertheless, the correlation between the strange and anapole contributions suggest that there is only a small probability that these form factors all vanish simultaneously.