Self-Amplified Spontaneous Emission Driven by a High-Brightness Electron Beam

Abstract

We report the first high-gain self-amplified spontaneous emission experiment at $15\ensuremath{\mu}\mathrm{m}$ driven by a high-brightness 17-MeV electron beam. A change of two decades in the beam current yields an increase of four decades in the measured infrared power. By fitting the measured infrared pulse energy to an analytic model, we estimate that eight power gain lengths, corresponding to a gain of 300, exist in the wiggler at 279 A.