PSI, Villigen
The resonant stripline pickup was chosen for a Beam Position Monitor (BPM) developed for the 250 MeV PSI XFEL Injector to reach the desired sensitivity of 10 micrometers in beam position. The electromagnetic design of this cavity, performed with Microwave Studio, was optimized in terms of the main radiofrequency characteristics - frequency, shunt impedance, Q value - of the resonant modes of interest, in order to obtain the pickup sensitivity required by the electronics (direct sampling, [*]). Also mechanical aspects of the design are presented, with particular attention to the solution adopted for the stripline alignment. Based on the simulated geometry, a pickup prototype was carried out and tested, allowing to verify the correct characteristics of the resonant modes and to state the present resonant stripline pickup design as one possible candidate for the standard (non-undulator) BPM system of the PSI XFEL and also for other linear accelerators or storage ring transfer lines.
[*]: B. Keil, S. Lehner. S. Ritt, "Application of a 5 GSPS Analogue Ring Sampling Chip For Low-cost Single-shot BPM Systems", Proc. EPAC 2008, Genoa, Italy, 1167 (2008).
PSI, Villigen
This contribution gives an overview of transverse sub-micron beam position measurement systems and techniques for 3rd and 4th generation light sources and collider projects. Topics discussed include mechanical, electrical and digital design aspects, environmental influences, machine operation and design considerations, as well as system- and beam-based measurement and calibration techniques.
PSI, Villigen
In this paper, we describe four very different operating modes of the SwissFEL facility, the requirements of the challenging beam diagnostics and ultra-stable RF systems needed for two special operating modes with 10 pC, and the present status of developing beam diagnostics and RF systems for the PSI 250 MeV injector test facility, which is under construction.