Sunao Takahashi

Construction and Commissioning of A 248 m‐long Beamline with X‐ray Undulator Light Source

A medium‐length beamline with undulator source, BL20XU at SPring‐8, was constructed, and opened to public use. The distance from source point to the end of the beamline is 248 m. By utilizing the long beam transport path, the beamline has advantages for experiment that requires high spatial coherence in hard X‐ray regions.

Construction and Commissioning of BL37XU at SPring-8

Trace element analysis beamline (BL37XU) at SPring‐8 was designed for application to various X‐ray fluorescence analyses such as XRF imaging, XAFS, TXRF and XRF holography. The beamline has of two branches, one being a SPring‐8 standard undulator‐beamline optics branch (Branch A) and the other a high‐energy branch (Branch B). In the experimental hutches, several kinds of experimental device are equipped. The end‐stations have been opened to public use since November 2002, and various experiments have been carried out.

Performance of a Highly Stabilized and High-resolution Beamline BL17SU for Advanced Soft X-ray Spectroscopy at SPring-8

A new soft x‐ray beamline BL17SU (RIKEN) has been constructed at SPring‐8. The beamline consists of two branches with each varied‐line‐spacing‐plane‐grating‐monochromator. Both monochromators perform high energy resolution (E/ΔE > 10,000) between 0.2 and 1 keV. One of the monochromator achieves high energy stability of 10 meV over a period of half a day.

Performance upgrade in the JAEA actinide science beamline BL23SU at SPring-8 with a new twin-helical undulator

The commissioning studies and an application to a uranium compound with the helicity-switching mode of a new twin-helical undulator installed in soft X-ray beamline BL23SU at SPring-8 are described.

New soft X-ray beamline BL07LSU at SPring-8

The design and performance of a new soft X-ray beamline BL07LSU at SPring-8 are described. The combination of a novel segmented cross undulator and beamline monochromator has achieved high energy resolution (E/ΔE > 10000) and high photon flux [>1012 photons s−1 (0.01% bandwidth)−1] in the photon energy range 250–2000 eV with fully controllable polarization.

New micro-beam beamline at SPring-8, targeting at protein micro-crystallography

A new protein micro‐crystallography beamline BL32XU at SPring‐8 is under construction and scheduled to start operation in 2010. The beamline is designed to provide the stabilized and brilliant micro‐beam to collect high‐quality data from micro‐crystals. The beamline consists of a hybrid in‐vacuum undulator, a liquid‐nitrogen cooled double crystal monochromator, and K‐B focusing mirrors with large magnification factor. Development of data acquisition system and end station consists of high‐precision diffractometer, high‐efficiency area detector, sample auto‐changer etc. are also in progress.

RISING beamline (BL28XU) for rechargeable battery analysis

The BL28XU beamline, dedicated to rechargeable battery analysis, is described.

Fatigue life prediction for high-heat-load components made of GlidCop by elastic-plastic analysis

A procedure to predict the fatigue fracture life of high-heat-load components made of GlidCop has been successfully established. This method is based upon the Manson-Coffin equation with a cumulative linear damage law. This prediction was achieved by consolidating the results of experiments and analyses, and considered the effects of environment and creep. A low-cycle-fatigue test for GlidCop was conducted so that environment-dependent Delta(t)-N(f) diagrams for any temperature could be prepared. A special test piece was designed to concentrate the strain in a central area locally, resulting in the low-cycle-fatigue fracture. The experiments were carried out by repeatedly irradiating a test piece with an electron beam. The results of the experiment confirmed that the observed fatigue life was within a factor of two when compared with the predicted fatigue life, yet located on the safer side.

Present Status and Performance of SPring-8 Front Ends

SPring-8 front ends have a novel structure which makes it easy to rearrange them and exchange the components. The structure has a common support for all the components except X-ray beam-position monitors and lead collimators. The alignment of the common support as well as the components was carried out with an accuracy of 0.25 mm in the vertical and horizontal directions. Replaceable pumping systems have also been placed on the common support and have achieved a vacuum of 2 x 10(-8) Pa at the upstream part of the front ends without synchrotron radiation. During the commissioning with synchrotron radiation, the pumping systems displayed good pumping-down characteristics. Commissioning has been successfully performed for four standard in-vacuum X-ray undulators and three bending-magnet-beamline front ends up to July 1997. Measurements of temperature rise show that absorber, pre-slits and XY slits can handle the anticipated maximum heat load at a ring current of 100 mA.

Synchrotron radiation x-ray beam profile monitor using chemical vapor deposition diamond film

Photoluminescence (PL) of a Si-doped polycrystalline diamond film fabricated using the chemical vapor deposition technique was employed to measure the profile of a synchrotron radiation pink x-ray beam emitted from an in-vacuum hybrid undulator at the SPring-8 facility. The spectrum of the section of the diamond film penetrated by the emitted visible red light exhibited a peak at 739nm and a wideband structure extending from 550to700nm. The PL intensity increased with the absorbed dose of the incident beam in the diamond within a dynamic range of 103. A two-dimensional distribution of the PL intensity revealed the undulator beam profile.