Electron micropulse diagnostics and results for the Los Alamos free-electron laser

The electron beam diagnostic used in the Los Alamos free-electron laser are described. These include the standard beam-current,-position and -profile monitors as well as more elaborate energy and temporal spectrometers. Emphasis is given to the latter devices, which provide three-dimensional representations of the electron beam current as a function of energy and time in the picosecond region. These results were used to determine the performance of the accelerator and the laser. Crucial accelerator parameters were the energy spread and temporal shape of the micropulse. Essential laser parameters were the extraction efficiency and the duration of lasing during an individual micropulse.