Bent-crystal Laue spectrograph for measuring x-ray spectra ( 15 < E < 100 keV )

• Published in: Review of scientific instruments 2006-10, Vol.77 (10), p.10F314-10F314-4
• Main Authors: Failor, B. H., Wong, S., Riordan, J. C., Hudson, L. T., O'Brien, C. M., Seltzer, S. M., Seiler, S., Pressley, L., Lojewski, D. Y.
• Format: Article
• Language: English
• Subjects: BIOMEDICAL RADIOGRAPHY; CHARGE-COUPLED DEVICES; CRYSTALS; ELECTRON BEAMS; ICF DEVICES; INERTIAL CONFINEMENT; INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; KEV RANGE; LITHIUM FLUORIDES; MAMMARY GLANDS; PHOTOMULTIPLIERS; RADIOLOGY AND NUCLEAR MEDICINE; REFLECTIVITY; RESOLUTION; SENSITIVITY; X RADIATION; X-RAY DIFFRACTION; X-RAY SOURCES; X-RAY SPECTRA; X-RAY SPECTROMETERS; X-RAY TUBES
• ISSN: 0034-6748; 1089-7623
• DOI: 10.1063/1.2229265

A bent-crystal Laue {or Cauchois [ J. Phys. Radium 3 , 320 ( 1932 ) ] geometry} spectrograph is a good compromise between sensitivity and spectral resolution for measuring x-ray spectra ( 15 < E < 100 keV ) from large area x-ray sources because source-size spectral broadening is mitigated. We have designed, built, and tested such a spectrograph for measuring the spectra from electron-beam x-ray sources with diameters as large as 30 cm . The same spectrograph geometry has also been used to diagnose (with higher spectral resolution) smaller sources, such as x-ray tubes for mammography and laser-driven inertial fusion targets. We review our spectrograph design and describe the performance of different components. We have compared the reflectivity and spectral resolution of LiF, and Ge diffracting crystals. We have also measured the differences in sensitivity and spectral resolution using different x-ray to light converters (plastic scintillator, CsI, and Gd 2 O 2 S ) fiber optically coupled to an intensified charge-coupled device camera. We have also coupled scintillating fibers to photomultiplier tubes to obtain temporal records for discrete energy channels.