The Design of Gridded Pierce Guns for Accelerators

Numerical and design technologies which have led to significant improvements in gridded Pierce guns (used in microwave tubes and electron linacs) are described. The design of a gridded triode Pierce gun is explained, with reference to the effects of the grid and to the importance of a deformable mesh code in the model simulations of the gun. The triode gun with postaccelerator and ultralaminar tetrode gun, which show enhanced performance over the standard triode Pierce gun, are discussed, stressing the importance of employing the ultralaminar beams in electron linacs to maximize charge transport.