DEMONSTRATION EXPERIMENT OF A LASER SYNCHROTRON SOURCE FOR TUNABLE, MONOCHROMATIC X-RAYS AT 500-EV

A demonstration experiment of the laser synchrotron source (LSS) is be ing planned and constructed to generate short-pulsed, tunable X-rays i n the range of similar to 500 eV by Thomson scattering of laser photon s from a relativistic electron beam. Laser photons of lambda = 1.06 mu m are Thomson backscattered by a 4.5 MeV electron beam from an S-band RF electron gun. The laser photons are derived from a 15 J, 3 ns Nd:g lass laser. The RF electron gun is being constructed for initial opera tion using a thermionic cathode. It will be upgraded with a photocatho de to produce high quality electron beams with high current and low em ittance. The X-ray pulse structure consists of similar to 10 ps long m icropulses within a laser pulse width dependent macropulse. The estima ted X-ray photon flux is similar to 10(18) photons/s, and the number o f photons per macropulse is similar to 10(8).