摘要
To measure magnetic fields with a Hall probe, accurate alignment needs to be considered. Therefore, we present improvements to Hall probe measurement system, including cone magnets and a zero-field shield as simulated by OPERA. The design of cone magnets of the North-face-North (N-N) type is greatly helpful to monitor magnet alignment. The accurate location of the Hall probe doping area should be determined before doing any measurements. In addition, a zero-field shielding tube is used to reset the probe to zero. Results of simulations are reported in this paper.