<title>Low-Gamma Continuously-Tunable Infrared (IR) Free-Electron Laser</title>

Abstract

Free electron lasers (FELs), based on stimulated emission of radiation by a relativistic electron beam, show potential as a new class of coherent radiation sources that are characterized by continuous tunability, high average power, and electrically efficient operation. Exploratory computer simulations of an FEL oscillator are presented for experimental conditions appropriate to a repetitively-pulsed Van de Graaff accelerator. A program to establish the feasibility of a continuously-tunable IR laser is also described, including discussions of two-stage and optically-pumped devices that promise attractive efficiency and power levels.