Speaker
Description
Plasma-based accelerators can produce accelerating fields several orders of magnitude stronger than those of conventional accelerators. They operate by driving density waves in a plasma using compact particle beams or laser pulses. The resulting strong wakefields are then used to accelerate a trailing electron bunch. The FLASHForward experiment at DESY performs fundamental research on this scheme using FEL-quality bunches from the FLASH linear accelerator. This contribution will summarise recent results from FLASHForward to provide insight into the state of beam-driven plasma accelerator research.
The trailing bunch can be injected internally from the plasma, a promising route to ultra-low emittance. Results from FLASHForward will be presented demonstrating reproducible density down-ramp injection and GV/m acceleration of bunches with collider-relevant quality.
Both matching into plasma-based accelerating stages and collider final-focusing systems require strong focusing fields. Fields of the required magnitude can be produced by passive plasma lenses. Experimental results will be discussed showing that such lenses can preserve FEL-quality transverse slice emittance and produce focusing fields two orders of magnitude stronger than permanent quadrupole magnets.
A novel diagnostic of the driver-to-witness energy-transfer efficiency will also be shown. Exploiting the emitted plasma light, the technique is parasitic and longitudinally resolved.
Finally, preliminary experimental results, including plasma acceleration, will be presented on generating twin bunches at the photocathode suitable for plasma wakefield acceleration with tunable delay and bunch shapes.