First operation of the Israeli Tandem Electrostatic Accelerator Free-Electron Laser

Abstract Results of first operation of the Israeli Electrostatic-Accelerator Tandem Free-Electron Laser (EA-FEL) are reported. This EA-FEL utilizes a 1.4 A electron beam obtained from a parallel flow Pierce-type electron gun. The e-beam is transported into a resonator located inside a planar Halbach configuration wiggler, which is at a potential of 1.4 MeV with respect to the cathode. A resonator utilizing two curved parallel plates as a waveguide and two Talbot effect quasioptical reflectors (wave splitters) provides a quality factor Q ≈30 000. Millimeter wave radiation pulses of 2 μs duration were obtained at a frequency of 100.5 GHz, as predicted, at a power level above 1 kW.