A. Dipace

Compact free-electron laser resonators utilizing electron-transparent mirrors

The potential advantages and the physical properties of several electron-transparent mirrors (e.g., metal meshes, thin foils, pierced mirrors, and Bragg reflectors) to be used in infrared free-electron laser resonators are reviewed. The conditions under which the effect on the electron beam quality can be kept small are discussed, and experimental results on the angular spread produced by a 2.5- mu m-thick metal mesh on a 5 MeV electron beam are presented. The experimental test of a resonator with two different electron transparent output couplers is reported. >

Status of the ENEA-Dartmouth far infrared Cherenkov laser experiment

Abstract In this article we report on the design parameters and status of the experiment of the ENEA-Dartmouth Cherenkov free electron laser. A brief analysis of the spontaneous emission process is also presented.

A 100 μm Cherenkov laser experiment

Abstract The basic operating principles of far infrared Cherenkov lasers are summarized and then used as a design guide for a proposed 100 μm region oscillator experiment. A discussion of the required accelerator and resonator parameters is presented and the preliminary experimental progress is reviewed.

Status report of the IR FEL project on the superconducting linac LISA at LNF-Frascati

Abstract We report the progress of the superconducting linac LISA at LNF (Frascati National Laboratories) and the status of the FEL experiment. The design of the optical cavity is presented.

A simple three‐dimensional free electron laser code

We present a simple and inexpensive computer code for free electron laser (FEL) operation that includes high gain and inhomogeneous broadening effects. The code is based on analytical formulae, obtained within the context of the theory of FEL approximants, requires negligible CPU time, and may run on small computers.

Compact FEL activity at the ENEA-Frascati Research Center

Abstract A 5 MeV FEL facility devoted to the testing of compact FEL devices has been realized at the ENEA Research Center of Frascati. In previous experiments power up to 50 W in 4 μs pulses has been generated in a Cherenkov FEL at wavelengths ranging from 0.8 to 1.6 mm using different dielectric guides. Current activities include the testing of short-period undulators in a small size waveguide FEL designed to operate in the sub-millimeter region. Operating characteristics and predicted performance are presented.

A far-infrared quasi-optical resonator for a Cherenkov free electron laser

Abstract A Cherenkov free electron laser experiment (Ch-FEL) employing a 5 MeV microtron electron-beam source and providing coherent radiation in the spectral range from 100 to 1000 μm is under way in our laboratories. Recent tests of a quasi-optical resonator are reported.

Progress report of the machine construction and FEL program on LISA at LNF

Abstract We report the construction progress of the superconducting (SC) linac LISA and of the FEL experiment SURF at LNF. The design criteria of the 25 MeV transport line from the linac to the undulator are presented and the operation and emittance measurements of the 100 keV gun are described.

The FEL project in the Frascati INFN laboratories with the linear SC accelerator LISA

Abstract A program to construct a test superconducting electron linear accelerator (LISA) is in progress at Frascati INFN National Laboratories. The electron beam will be used to realize an FEL in the infrared region (11–18 μm) in collaboration with a group of ENEA-CRE Frascati. The electron beam parameters and their relation to the expected performances of the FEL are discussed. Some future developments — energy recovery, energy doubling — are briefly presented.

Waveguide tapering for FEL in the high gain regime

Abstract A free electron laser (FEL) operation in the far infrared or millimeter wave region of the spectrum requires the use of a waveguide to confine the radiation. A new tapering scheme for the operation in the high gain regime, in the amplifier configuration, can thus be utilized in which the waveguide gap is varied while the undulator magnetic field and period are kept constant. The results of a numerical code are presented.