Flux-gate magnetometer for determinaton of beam center of gravity position of 30-500 ns high-current beam duration

For monitoring of the LiU-3000 electron beam the flux-gate mgnetometer for determining the beam center of gravity position has developed. The magnetometer is highly protected against the electromagnetic noise ad has relatively low sensitivity to the asymmetry of the currents in the magnetometer screen. The magnetometer consists of two pars of windings placed on a rectangular cross section toroidal core. Every coil is screened by the interior screen with aximuthal cut and plates in cross sections. The screened coils are located in a usual cuted proective scree. The diameter of drift aperture is 97 mm. The magnetometer signas enter the converter and after that to the computer where the beam position and current are calculaed. The test results of the magnetometer parameters and their analysis are also described. The magnetometer parameters are as follows: X and Y resolution in the circl with R=3 cm is not worse than 1 mm; variations of the frequency response in the (0-150)MHz range is not more than 5 dB; integration constant is 2.4x10sup(-6) s for the ferrite core coils (300 NN) and 0.88x10sup(-6)s for the plexiglass core coils