A measurement of parity-violating asymmetry with polarized electrons scattered from protons and implications for strange form factors

We have measured the parity violating asymmetry with polarized electrons scattered elastically from protons. The result is A = −15.05 ± 0.98(stat) ± 0.56(syst) ppm at the kinematic point ⟨&thetas;_lab⟩ = 12.3° and ⟨Q2⟩ = 0.477( GeV/c)2. The value for the linear combination of the strange form factors found using A is $GsE$ + 0.392$GsM$ = 0.025 ± 0.020 ± 0.014 where the first error is experimental and the second stems from the uncertainties in the electromagnetic form factors.