Generation of narrow-band low frequency radiation via laser-generated electron bunches and resonant cavities

Abstract It is shown that the single transit of a laser-generated electron bunch can generate strong, narrow-band radiation in a resonant cavity. This is shown numerically for an electron bunch relevant to those produced by laser wakefield acceleration. The bunch can also transit through two adjacent cavities and generate radiation in both. The phase relation between the radiation in the two cavities is well defined implying that coherent combination of radiation from multiple cavities is theoretically achievable.