VISA Status
Page updated on Au
gust 02, 2001
VISA has demonstrated a gain of 2.2×107, and an exponential growth rate (intensity gain length) of 18.5 cm. Saturation of the FEL intensity was observed at about 3.6 m from the undulator entrance. The experiment was done using a 71 MeV high brightness electron beam, with a peak current of about 70 A, a normalized projected emittance of about 1.7 mm mrad, at a radiation wavelength of 8 30 nm. The results indicate that the gain depends on the slice emittance, and that the slice emittance is substantially smaller than the projected emittance.