NUCLEON STRUCTURE UNCERTAINTIES IN PARITY-VIOLATING QUASI-ELASTIC ELECTRON-SCATTERING

We investigate the nucleon structure uncertainties for the extraction of the parity-violating asymmetry measured at Mainz by means of the 9Be(e, e′) reaction. We demonstrate that the contribution to the asymmetry from the quasi-elastic region is only mildly affected by the changes in the electromagnetic and axial nucleon form factors and by possible strangeness admixtures into the nucleon wave function. These nucleon structure effects do not alter the existing bounds on the weak neutral hadronic axial-vector coupling constants. The largest uncertainty actually arises from the neutron charge form factor. Similar conclusions can be drawn for the elastic electron-12C scattering experiment at Bates. © 1990.