First- and higher-order noninterference QED radiative corrections to the charge asymmetry at theZresonance

A variety of analytical and numerical results on the noninterference QED O(α) and O(α²) corrections to forward-backward (charge) asymmetry AFB are presented. Three definitions of the scattering angle and six definitions of the AFB are examined. For loose cutoffs, at the Z position, the pure O(α²) noninterference correction is found to be δAFB8×10^-3 with the theoretical uncertainty below {~}1 ×{} 10^-3. All numerical and analytical calculations can be parametrized using a simple semianalytical formula: AFB to within δAFB8×10^-3 on the Z resonance and {}0.5 ×{} 10^-2 off the resonance, MZ-5 GeV<√s<MZ+5 GeV; the differential distribution dσdcosθ to a relative precision of 5 ×{} 10^-3. These results can be very useful for (i) quantitative parametrization of the exact Monte Carlo results, (ii) discussion of the electroweak corrections, and (iii) experimental data analysis.