Schematic diagram of the Korean-XFEL

Figure 1. Schematic diagram of the Korean-XFEL.


The generation of an isolated attosecond pulse at 0.1 nm has been proposed in an ESASE scheme where an 800 nm, 5 fs FWHM carrier-envelop-phase stabilized laser is employed in the 10 GeV Pohang accelerator laboratory—x-ray free electron laser (PAL-XFEL). The radio-frequency (RF) phase effect has been studied on the current profile after the chicane and on the x-ray radiation power at 50 m along the undulator. This study leads to the tolerance in the RF phase. The results show that a single isolated attosecond radiation pulse could be produced inside the undulator; however, the RF phase should be controlled down to 0.05° in the linac section of the PAL-XFEL in order to satisfy the requirement for RF jitters suitable for pump–probe experiments.