Laser-plasma accelerators (LPAs) generate ultrashort, high-intensity electron bunches in a compact form factor. At Karlsruhe Institute of Technology (KIT), we are developing an LPA for direct injection into a specifically built storage ring with high momentum acceptance. The cSTART storage ring (compact storage ring for accelerator research and technology) can be tuned to energies between 50 – 90 MeV, and its lattice is designed to accept electron beams with +/- 4% energy spread. Furthermore, the ring lattice can be set up for the storage of ultrashort electron bunches. The LPA electron injector must be readily tunable to match the storage ring parameters. This contribution reports proof-of-concept experiments that demonstrate the generation of high-quality LPA electron beams with parameters that fulfill the cSTART requirements.

Laser-plasma accelerators (LPAs) generate ultrashort, high-intensity electron bunches in a compact form factor. At Karlsruhe Institute of Technology (KIT), we are developing an LPA for direct injection into a specifically built storage ring with high momentum acceptance. The cSTART storage ring (compact storage ring for accelerator research and technology) can be tuned to energies between 50 – 90 MeV, and its lattice is designed to accept electron beams with +/- 4% energy spread. Furthermore, the ring lattice can be set up for the storage of ultrashort electron bunches. The LPA electron injector must be readily tunable to match the storage ring parameters. This contribution reports proof-of-concept experiments that demonstrate the generation of high-quality LPA electron beams with parameters that fulfill the cSTART requirements.

Radiofrequency linacs accelerate thousands of bunches per second, which should be matched by beam-driven plasma wakefield accelerators (PWFAs) if their benefits as high-acceleration-gradient energy boosters are to be fully exploited. However, demonstrations to date have accelerated only ~10 bunches per second. At FLASHForward, key issues are being solved to bridge this gap. Analytic models have been developed to show how to generate bunch pairs from the photocathode with the longitudinal shape optimised for plasma acceleration, thus reducing stray radiation compared to a collimator system. To deal with large energy depositions from rapid plasma creation and acceleration events benchmarked models have been built to determine the heating of the plasma source at kHz repetition rates, so that remedial measures can be developed. Furthermore, we have seen that ionisation induced by the wakefield-perturbed plasma can limit the maximum repetition rate. Finally, PWFAs must produce large energy gains for photon science or particle physics applications. We recently demonstrated acceleration of bunches from 1.2 to > 1.7 GeV over 0.5 m of plasma, with < 2% energy spread.

DESY draws on more than six decades of experience in the development, operation, and radiation protection of large-scale user facilities such as PETRA III, FLASH, and the European XFEL. In parallel, the investigation of novel accelerator technologies for future applications has become a key focus. Laser-plasma acceleration (LPA) offers the potential for highly compact, high-gradient sources, as demonstrated by the LUX, KALDERA, and FORWARD facilities at DESY. However, LPA systems introduce new challenges for radiation protection due to broadband emission spectra and the interplay of high-power lasers with plasma-generated secondary radiation fields. This contribution presents the radiation-protection concept for LPA facilities at DESY, covering shielding simulations and designs with a focus on the differences com-pared to conventional electron accelerators. Finally, operational experience from commissioning the KALDERA LPA and further development stages is discussed, illustrating practical implementation.