A 36-pixel tunnel junction soft x-ray spectrometer for scintillator material science

作者：Friedrich Stephan^*; Drury Owen B; Yuan Shaopang; Szupryczynski Piotr; Spurrier Merry A; Melcher Charles L

来源：IEEE Transactions on Applied Superconductivity, 2007, 17(2): 351-354.

DOI：10.1109/`TASC.2007.898725

• cerium activators
• oxidation states
• superconducting tunnel junctions
• superconducting X-ray detectors
• X-ray absorption spectroscopy

We have built a 36-pixel superconducting tunnel junction (STJ) spectrometer for high-resolution soft X-ray spectroscopy at the synchrotron. It has an energy resolution between similar to 10 and similar to 20 eV FWHM for X-ray energies below similar to 1 keV, and can be operated at maximum total count rates of similar to 10(6) counts/s. For increased sensitivity, we have modified the detector cold finger the so that the array now subtends a solid angle of Omega/4 pi approximate to 0.1%. The spectrometer is currently used at the Advanced Light Source synchrotron for speciation measurements of dilute samples by fluorescence-detected X-ray absorption spectroscopy. We present measurements of the oxidation state of dilute cerium activators in novel scintillator materials, determine the Ce3+/Ce4+ ratio, and discuss the sensitivity of the instrument for quantitative speciation measurements.

• 出版日期2007-6