Fresh-slice double-pulses X-ray Free Electron lasers

Program Description

The technique of fresh-slice allows generating intense ultra-short double pulses for pump-probe experiments with control over the delay, color separation and pointing. The technique is based on an electron bunch time-dependent trajectory impressed by the transverse wakefield of a corrugated structure and subsequent orbit manipulation in the undulator section.

Color separation can be controlled by the undulator strength in the different undulator sections, and delay can be controlled with the magnetic chicanes.

Distinct advantages of this scheme are fully saturated intensities in both short pulses, possibility of scanning the probe delay smoothly through zero and independent control over pulse delay and color separation.

Fresh-slices open up the possibility of fresh-bunch self-seeding schemes and multi-color FELs.