R. Prazeres et al., OBSERVATION OF SELF-AMPLIFIED SPONTANEOUS EMISSION IN THE INFRARED FREE-ELECTRON LASER CLIO, Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment, 393(1-3), 1997, pp. 326-331
A solution has been proposed about ten years ago to reach the X-ray ra
nge: the principle is to operate the FEL in the Self-Amplified Spontan
eous Emission (SASE) configuration. In the high gain regime, the spont
aneous emission is amplified along the undulator in a single pass conf
iguration and without optical cavity. We report here the observation o
f SASE at the shortest wavelength the mid-infrared range. A spectral a
nalysis of the SASE has been carried-out in the start-up regime of SAS
E, far from the saturation level.