Speaker
Summary
We present an experimental setup strategy for the realization of an
optical free-electron laser (OFEL) in the Traveling-Wave Thomson-
Scattering geometry (TWTS). In TWTS, the electric field of petawatt
class, pulse-front tilted laser pulses is used to provide an optical undulator field. This is passed by a relativistic electron bunch so that
electron direction of motion and laser propagation direction enclose an
interaction angle. The combination of side scattering and pulse-front
tilt provides continuous overlap of electrons and laser pulse over meter
scale distances which are achieved with centimeter wide laser pulses.
An experimental challenge lies in shaping of these wide laser pulses in
terms of laser dispersion compensation along the electron trajectory
and focusing. The poster shows how diffraction gratings in combination with mirrors are used to introduce and control dispersion of
the laser in order to provide a plane wave laser field along the electron
trajectory. Furthermore we give limits on alignment tolerances to
operate the OFEL. Example setups illustrate functioning and demonstrate feasibility of the design.
