Förster, D.; Lindenau, B.; Leyendecker, M.; Janssen, F.; Winkler, C.; Schumann, F.O.; Kirschner, J.; Holldack, K.; Föhlisch, A.: Phase-locked MHz pulse selector for x-ray sources. Optics Letters 40 (2015), p. 2265-2268
10.1364/OL.40.002265
Open Access Version (externer Anbieter)
Abstract:
Picosecond x-ray pulses are extracted with a phase-locked x-ray pulse selector at 1.25 MHz repetition rate from the pulse trains of the accelerator-driven multiuser x-ray source BESSY II preserving the peak brilliance at high pulse purity. The system consists of a specially designed in-vacuum chopper wheel rotating with ≈1 kHz angular frequency. The wheel is driven in an ultrahigh vacuum and is levitated on magnetic bearings being capable of withstanding high centrifugal forces. Pulses are picked by 1252 high-precision slits of 70 μm width on the outer rim of the wheel corresponding to a temporal opening window of the chopper of 70 ns. We demonstrate how the electronic phase stabilization of ±2 ns together with an arrival time jitter of the individual slits of the same order of magnitude allows us to pick short single bunch x-ray pulses out of a 200 ns ion clearing gap in a multibunch pulse train as emitted from a synchrotron facility