Effect of the nonlinear compression of ultrashort microwave pulses in the process of the amplification by quasistationary electron beams

An effect of the nonlinear compression of ultrashort microwave pulses has been observed in the process of the amplification of quasistationary electron beams. The Cherenkov mechanism of the interaction of a rectangular electron beam with a decelerated wave in a waveguide partially filled with an insulator is used. The experiment has been conducted on a setup consisting of two synchronized RADAN high-current accelerators. The first accelerator supplied a generator of 37-GHz superradiance pulses with a duration of about 300 ps. The second accelerator with a beam current of up to 1.2 kA and an electron energy of about 300 keV was used in an amplifying section. The theoretical analysis shows that the amplification of the electromagnetic pulses (at least by a factor of 4 in the power) is accompanied by a strong decrease in their duration (down to 100 ps).