Theoretical analysis of the offset-pole periodic cusped permanent magnetic fields
偏置磁极周期会切永磁场的理论分析

The magnetic field excited by the offset-pole periodic cusped permanent magnet (OPPCPM) used for focusing the sheet electron beam has been approximately expressed in two different forms for the convenience of future numerical calculation and theoretical analysis, respectively. Firstly, the surface-current-sheet model has been used to approximate the OPPCPM, and an accurate expression has been obtained using Biot-Savart law. This expression would rather be applied to numerical calculation than theoretical an...