Cyclotron autoresonance maser with helical electron guiding center

摘要

A cyclotron autoresonance maser includes an evacuated drift tube with a first end, a second end and an axis. An electron gun introduces a beam of relativistic electrons to the drift tube first end and, for example, a wiggler magnet causes the electrons to gyrate with the gyrations having relatively small radii. A magnetic field generator is provided which forces the beam of relativistic, gyrating electrons to spiral about the axis of the drift tube. The radii of the spirals is large relative to the radii of the gyrations so that the effective interaction length of the electron beam and a maser beam, having an axis substantially coincidental with the axis of the electron beam, is substantially greater than that of a relativistic electron beam and a maser beam which simply cross. A method of generating coherent radiation is also disclosed.