Uncertainty in intense pulse electron beam position monitor

Beam position as a key parameter of intense electron beam linear induction accelerator，is criterion of electron beam tuning and experiment. The resistive ring monitor(RRM) and B-dot monitor are often used to measure the beam current and position simultaneously. According to the measuring principle, the calibration method and characters of monitor, type A and type B standard uncertainties and least square fit uncertainty were analyzed as the uncertainty sources of beam position monitors RRM and B-dot, and their evaluation were decided. The combined standard uncertainty of Dragon- resistive ring monitor and B-dot is less than 0.1mm based on calibrating data.