JASRI/SPring-8, Hyogo-ken
SES, Hyogo-pref.
We have developed a kicker magnet system including a compact power supply to generate short pulse synchrotron radiation in the SPring-8 storage ring. One method to generate the short pulse synchrotron radiation is cutting out a synchrotron radiation coming from an tilted electron bunch with a slit. For this purpose, we induced a head-tail oscillation of an electron bunch due to non-zero vertical chromaticity excited by using a pulsed magnetic field. By using this scheme, the required specification to the magnet system is relaxed which leads to reduction of construction cost. Developed kicker magnet system can generate a short pulsed vertical field of about 3.6 mT within the 3 us to an electron bunch at 1 Hz repeat. With the kicker magnet system, we successfully observed a bunch profile which leans about 2 mm between head and tail position by a streak camera. We will report the detail setup of the kicker magnet system including compact power supply and the measurement system of beam profile, then discuss the comparisons between real beam motion and simulation results.
RIKEN Spring-8 Harima, Hyogo
JASRI/SPring-8, Hyogo-ken
RIKEN/SPring-8, Hyogo
In XFEL/SPring-8, it is very important to generate an electron beam, having a low slice emittance of 0.7 pimm-mrad, a pulse width of 30 fs, and a peak current of 3 kA at an X ray lasing part. For tuning such beam to guarantee stable X ray laser generation, beam and laser monitors to diagnose the temporal structure of them are an indispensable function. The monitors, such as a beam position monitor (BPM), a TM11-mode rf beam deflector and a screen monitor (SCM), have been developed to satisfy the function. The BPM has a position resolution of less than 1 um. The SCM to observe the beam deflecting image has a position resolution of 2.5 um. The design of a longitudinal beam diagnosis system using the monitors showed that it can measure a temporal structure with a resolution of 0.5 fs along the beam pulse. The experiment to check feasibility of the BPM showed that it can work as a beam arrival timing monitor with a temporal resolution of 46 fs. A monitor system using an in-vacuum photo diode was also developed to measure the laser arrival timing, and showed ability to resolve a 2 ps time jitter. These temporal resolutions allow us fine beam tuning required for the XFEL.
RIKEN/SPring-8, Hyogo
JASRI/SPring-8, Hyogo-ken
The SPring-8 compact SASE source (SCSS) test accelerator was constructed in FY2005 to demonstrate a new concept for X-ray free electron lasers composed of a low-emittance thermionic electron injector, a high-gradient normal conducting C-band accelerator, and a short-period in-vacuum undulator. With a 250 MeV electron beam, continuous SASE saturation can generate intense and stable FEL beams at the wavelength range from 50 to 60 nm with the maximum pulse energy of 30 micro-J and the intensity fluctuation of ~10%. Analysis of the SASE saturation data with a 3D-FEL simulation code suggests negligible degradation of the electron beam emittance during the high bunch compression process. We also succeeded in operating the C-band accelerator with a high accelerating gradient of 37 MV/m and a repetition rate of 60 pps. Now, the FEL beam is routinely delivered for user experiments. At this conference we will present the machine performance and recent progress of the SCSS test accelerator together with the anticipated performance of the 8 GeV XFEL under construction.
