Compact Optical Free Electron Laser with Traveling-Wave Thomson Scattering

We present a fully analytical description of the field and the electrons in an optical free electron laser in the Travelling-Wave Thomson Scattering (TWTS) configuration. This scheme allows for long interaction lengths of an ultra-short, high-intensity pulsed laser with an electron bunch. The latter can be either provided by laser-accelerated electrons or by a conventional accelerator. TWTS provides for high peak brightness, high brilliance pulses from the EUV to the gamma spectrum with high flexibility in the wavelength and bandwidth of the emitted radiation.