Pulse shortening by RF breakdown in relativistic backward wave oscillator

Relativistic backward wave oscillator (RBWO) is the suitable source for generating high power electromagnetic wave (HPEM). The RBWO has a high efficiency by means of the interaction region between a backward wave and an electron beam. However, the pulse shortening problem occurs frequently in experiments of RBWO because of the RF breakdown on rippled slow wave structure. Experimental study is done 500 MW RBWO in progress.