Effects of slows wave structure parameters on linear growth rate of coaxial relativistic baorward-wave oscillator

This paper derives the dispersion equation and the linear growth rate formula of the coaxial relativistic baorward-wave oscillator(RBWO) according to the linear theory. The effects of the ripple period and ripple depth on the linear growth rate of the coaxial RBWO are presented. It is found that when the ripple period decreases or the ripple depth increases in a certain range, the phase velocity of the microwave decreases but the linear growth rate increases.