Large orbit cyclotron autoresonance maser amplifier with outer-slotted-coaxial waveguide

The linear kinetic theory and nonlinear self-consistent model for outer-slotted-coaxial waveguide cyclotron autoresonance maser(CARM) amplifiers with axis-encircling beam are presented. Good agreement is found between the simulations and the kinetic theory in the linear regime. The choice of the electron beam current is discussed for suppressing the absolute instability. Using a 700 kV, 100 A axis-encircling beam with electron beam velocity pitch of 0.8, nonlinear self-consistent analysis predicts that TE51 CARM amplifier can have a peak output power of 6.27 MW and a peak efficiency of 8.96 %.