Atomic parity violation measurements in the highly forbidden 6S1/2-7S 1/2 caesium transition. II. Analysis and control of systematic effects

The parity-violating signal is discriminated by its specific behaviour when the handedness of the experiment is reversed Yet conspiracy of experimental imperfections can generate false parity signals. We establish a model of systematic effects, whose parameters are the imperfections in the handedness reversals realized experimentally. We describe how their actual values are measured and minimized, mostly by continuous control of atomic signals during data acquisition. This allows estimation and reduction of possible systematic effects. These remain finally at or below a few percent of the PV effect. We estimate possible limitations in the real-time controls, or in the model itself (e.g. due to spatial correlations in the imperfections). These limitations, together with statistical uncertainties in the controls, will be included in the final systematic uncertainty (Part III).