Abstract

As an alternative to the FEL for energy exchange between a relativistic electron beam and laser light, the inverse Cerenkov effect was investigated, wherein the phase velocity of an electromagnetic wave was retarded in a gaseous medium. By intersecting the laser and electron beams at the Cerenkov angle θ_c = cos⁻¹(1/nβ), the electrons remain in a field of constant phase, resulting in a cumulative energy exchange. The parameter n is the index of refraction of the medium, and β is the ratio of the electron velocity to the velocity of light in vacuum.

© 1981 Optical Society of America