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Brilliant pulsed x-ray synchrotron radiation (SR) is useful for pump-probe experiment such as time-resolved x-ray diffraction, x-ray absorption fine structure, and x-ray spectroscopy. For laser pump-SR x-ray probe experiments, short pulsed lasers are generally synchronized to the SR master oscillator controlling the voltage for acceleration of electron bunches in an accelerator, and the interval between the laser and the SR pulses is changed around the time scale of target phenomenon. Ideal delay control produces any time delay as keeping the time-precision and pointing-stability of optical pulses at a sample position. We constructed the time delay control module using a continuous phase shifter of radio frequency signal and a frequency divider, which can produce the delayed trigger pulses to the laser without degradation of the time precision and the pointing stability. A picoseconds time-resolved x-ray diffraction experiment was demonstrated at SPring-8 storage ring for fast lattice response by femtosecond pulsed laser irradiation, and suggested the possibility of accurate sound velocity measurement. A delay control unit operating with subpicosecond precision has also been designed for femtosecond pump-probe experiments using a free electron laser at SPring-8 campus. [ABSTRACT FROM AUTHOR]

We have developed a high-speed and simultaneous photon beam diagnostic system using optical cables at SPring-8. The system is composed of blade type X-ray beam position monitors (XBPM) in front ends, optical cables spread over the experimental hall and multi A/D converters at the photon beam diagnostic station. Analog data of the beam positions are transferred through the optical cables. The multi A/D converter allows us to browse and process the data from the main control room in real time. The features of the system are the wide band-width, the ability of full-time observation with XBPMs and the compatibility to the monitoring system of electron beam position monitors in the storage ring. The system has been routinely used for high-speed and simultaneous measurements of photon beam and electron beam. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]