BPM System Development and Applications in Commission of SXFEL-UF
B. Gao
SARI-CAS, Pudong, Shanghai, People’s Republic of China
J. Chen, Y.B. Leng
SSRF, Shanghai, People’s Republic of China
SXFEL is a soft X-ray free electron laser user facility that is current being commissioned in Shanghai. It is based on a 1.5 GeV normal conducting high gradient C-band (linear accelerator) LINAC and contains two FEL beamline, a seeded FEL beamline and a SASE beamline, and five experimental stations. The performance of X-ray FEL depends strongly on the quality of the electron beam and single shot stability. We have developed a BPM system including SBPM and CBPM. The resolution of SBPM is better than 4μmeters, and the resolution of CBPM is better than 176 nm. Because of its excellent position resolution, it plays an important role in the SASE beamline commissioning. The beam adjusters rely on this system to find and maintain an ideal track, and complete the debugging of the SBP beamline within 21 days. This paper presents the system design, methods used to determine the resolution, the performance, and the applications of those BPMs.
Right click on video for Picture-in-Picture mode or Full screen display.
Research on the Optimal Amplitude Extraction Algorithm for Cavity BPM
48
J. Chen, Y.B. Leng, T. Wu, Y.M. Zhou
SSRF, Shanghai, People’s Republic of China
S.S. Cao, B. Gao
SARI-CAS, Pudong, Shanghai, People’s Republic of China
The wake field of different modes of cavity BPM carries different bunch information, the amplitude and phase of the signals of different modes can be extracted through the signal processing method to obtain the characteristic parameters of the source bunch. In the application of bunch charge and position measurement, the accurate amplitude extraction method for cavity BPM signal is the primary issue to be considered when designing the data acquisition and processing system. In this paper, through theoretical analysis and numerical simulation, it is proved that the optimal algorithm of amplitude extraction for CBPM exists, and the dependence between the data processing window size and the decay time of the cavity BPM under the optimal design is given. In addition, the relationship between the optimized amplitude extraction uncertainty and the noise-to-signal ratio, sampling rate of data acquisition and processing system, and the decay time of the cavity BPM is also proposed, which can also provide clear guidance for the design and optimization of the CBPM system.
The First Beam Experiment Result of the Protype of Wire Scanner for SHINE
232
F.Z. Chen, J. Chen, B. Gao, Y.B. Leng
SSRF, Shanghai, People’s Republic of China
J. Wan
SINAP, Shanghai, People’s Republic of China
As a kind of quasi-non-destructive beam size monitoring, SHINE will employ dozens of wire scanners. The preliminary study is confronted with motion control difficulty. To reduce the ultrahigh coordinate about wire movement with beam loss data acquisition, a new method has been proposed in the SXFEL test platform. The strategy is utilizing the beam jitter, which is of the same magnitude with the beam size. Combine with the jitter of the beam position, we move tungsten wires in a few of different position to realize the measurement. This paper will present our experiment design as well as a furthermore plans about the prototyping design.
