Quantum mechanics

Beam (structure)

Full width at half maximum

Materials science

Computational physics

Nuclear physics

Energy (signal processing)

Atomic physics

Plasma

Laser

Physics

Plasma acceleration

Optics

Energy density

Excited state

Cathode ray

Acceleration

Electron

Engineering physics

Physical Review Letters

A tunable plasma-based energy dechirper has been developed at FLASHForward to remove the correlated energy spread of a 681 MeV electron bunch. Through the interaction of the bunch with wakefields excited in plasma the projected energy spread was reduced from a FWHM of 1.31% to 0.33% without reducing the stability of the incoming beam. The experimental results for variable plasma density are in good agreement with analytic predictions and three-dimensional simulations. The proof-of-principle dechirping strength of 1.8 GeV/mm/m significantly exceeds those demonstrated for competing state-of-the-art techniques and may be key to future plasma wakefield-based free-electron lasers and high energy physics facilities, where large intrinsic chirps need to be removed.

Tunable Plasma-Based Energy Dechirper