Improving the Performance of an Ultrashort Soft X-ray Free-Electron Laser via Attosecond Afterburners

In this study, we implement attosecond afterburners in an ultrashort soft X-ray free-electron laser (FEL) to improve the performance of generating pulses. scheme, FEL pulse produced normal radiator section is dumped while well bunched electron beam reserved and reused downstream afterburners. Subsequently, radiation gains rapidly as bunching factor current spike large, making much shorter cleaner than that from a radiator. Multi-shot simulations are carried out demonstrate stability proposed technique.