Error and jitter effects on BEPCⅡ-linac

To control the BEPCⅡ-linac beam performance within the upgrading goals, the error effects such as the initial beam offset and the accelerator misalignment effects on the beam performance have been systematically studied with beam modeling. The most important operating jitter effects including the phasing drift jitter and the modulator's jitter effects have also been studied. The tolerances of the errors and jitters have been decided and the effective beam orbit correction scheme is further confirmed. By controlling the initial beam offset from the electron gun within ±0.3 mm, the tolerance of the accelerating structures and quadruple misalignment within ±0.2 mm, the phase drift error within ±2°, and the modulator's voltage jitter within ±0.1%, and by employing the phase control syste