Demonstration experiment of a laser synchrotron source for tunable, monochromatic X-rays at 500 eV

Abstract A demonstration experiment of the laser synchrotron source (LSS) is being planned and constructed to generate short-pulsed, tunable X-rays in the range of ∼500 eV by Thomson scattering of laser photons from a relativistic electron beam. Laser photons of λ = 1.06 μ 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:glass laser. The RF electron gun is being constructed for initial operation using a thermionic cathode. It will be upgraded with a photocathode to produce high quality electron beams with high current and low emittance. The X-ray pulse structure consists of ∼10 ps long micropulses within a laser pulse width dependent macropulse. The estimated X-ray photon flux is ∼10 18 photons/s, and the number of photons per macropulse is ∼10 8 .