High energy beamlines

Scattering on the Triple-Axis-Diffractometer [1,2] at the HASYLAB high-energy beamline BW5 is performed in the horizontal plane using an Eulerian cradle as sample stage and a germanium solid-state detector. The beam is monochromatized by a singlecrystal monochromator (e.g. Si 111, FWHM 5.8 ), focused by various slit systems (Huber, Riso) and iron collimators and monitorized by a scintillation counter. The instrument is controlled by a p-VAX computer via CAMAC. 

Fig. 15.4. High energy beamline featuring an RF linac with 12 resonators. The ion source and analyzer magnets are on the left. The final energy magnet is on the right...

X-ray absorption experiments were carried out on the beamline BL-lOB at Photon Factory in the Institute of Materials Structure Science for High Energy Accelerator Research Organization, Tsukuba, Japan, with a ring current of 2.5 GeV and a stored current of 250 - 450 mA (Proposal Number 2005G194). Pt... 

The limited application of positron beams is explained by the fact that Doppler-broadening spectroscopy is the only detection method that works with beams without any difficulty. Although angular correlation measurements are possible with positron beams, it requires a very high efficiency beamline. Only very few beams fulfill the requirements of ACAR measurements, but their results are very impressive. The combination of low-energy positron beams and 2D-ACAR measurements is the only possibility to gain direct information on the momentum distribution of electrons at the surface of metals and semiconductors (Chen et al. 1987). 

The source is optimized to put large quantities of high-energy photons into a very small area in a very short time. With more than 40 beamlines already operational, and more under development, the APS offers an exceptionally broad range of experimental conditions at a single facility. Each beamline at the APS offers a unique combination of capabilities, but some of the main considerations are energy range and tunability, special sample environments, time structures, and beam size. 

Fig. 12.11 O Is X-ray absorption spectroscopy (XAS) spectra of BaCeo.9Yo.1O3 and BaCeo,825Yo.iRuo.o7503 a. measured at room temperature. The spectra (a) and (b) are of BaCeo.gYo.iOs and BaCeo.825Yo.iRuo.o7503 a respectively, untreated after sintering in moist air and thus reflecting the nature in an oxidative atmosphere the spectra (c) and (d) are of those annealed in moist 1%H.2 diluted by Ar at 800°C for 10 h exhibiting the electronic structure in the reducing atmosphere. V.B. and C.B., the positions of the top of the valence band and the bottom of the conduction band, respectively [35]. The measurements were conducted at the revolver undulator beamline BL-19B at the Photon Factory of the High Energy Accelerator Research Organization, Tsukuba, in Japan. (Reprinted from [35] with permission from Electrochemical Society)...

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