Features of Focusing Electron Beams by Guns with a Field at the Cathode

Investigations were made of the effect of the magnitude of the magnetic field at the cathode on the characteristics of the electron beam. It was shown that with an increase in Bc to 4 mTl, no change in the adjustment of B1-B3 values is required, since the change in pulsations and average radius is less than 10%. However, for Bc ≥ 6 mTl, it is necessary to tuning the matching of the beam with MPFS. To minimize the spread of Bc values, it is proposed to adjust the existing technology for magnetizing MPFS.