Improvements to the X-ray Spectrometer at the Aerosol Laboratory, Instituto de Física, UNAM

  • L V Mejía-Ponce Institute of Physics, National Autonomous University of Mexico (UNAM), PO Box 20-364, 01000 Mexico City, Mexico
  • A E Hernández-López Institute of Physics, National Autonomous University of Mexico (UNAM), PO Box 20-364, 01000 Mexico City, Mexico
  • S Reynoso-Cruces Institute of Physics, National Autonomous University of Mexico (UNAM), PO Box 20-364, 01000 Mexico City, Mexico
  • J C Pineda Institute of Physics, National Autonomous University of Mexico (UNAM), PO Box 20-364, 01000 Mexico City, Mexico
  • J A Mendoza-Flores Institute of Physics, National Autonomous University of Mexico (UNAM), PO Box 20-364, 01000 Mexico City, Mexico
  • J Miranda Institute of Physics, National Autonomous University of Mexico (UNAM), PO Box 20-364, 01000 Mexico City, Mexico
Keywords: X-ray fluorescence analysis, Silicon DriftDetector SDD, chemical composition of atmospheric aerosols, Standard Reference Material 2783

Abstract

Due to the demands of better (accurate and precise) analytical results using X-ray Fluorescence (XRF) at the Aerosol Laboratory, Instituto de Física, UNAM, it was necessary to carry out improvements in instrumentation and analytical procedures in the x-ray spectrometer located in this facility. A new turbomolecular vacuum system was installed, which allows reaching the working pressure in a shorter time. Characteristic x-rays are registered with a Silicon Drift Detector, or SDD, (8 mm thick Be window, 140 eV at 5.9 keV resolution), working directly in a high-vacuum, permitting the detection of x-rays with energies as low as 1 keV (Na Ka) and higher counting rates than in the past. Due to the interference produced by the Rh L x-rays emitted by the tube normally used for atmospheric and food analysis with Cl K x-rays, another tube with a W anode was mounted in the spectrometer to avoid this interference, with the possibility to select operation with any of these tubes. Examples of applications in atmospheric aerosols and other samples are presented, to demonstrate the enhanced function of the spectrometer. Other future modifications are also explained.

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Published
2018-08-06
How to Cite
L V Mejía-Ponce, A E Hernández-López, S Reynoso-Cruces, J C Pineda, J A Mendoza-Flores, & J Miranda. (2018). Improvements to the X-ray Spectrometer at the Aerosol Laboratory, Instituto de Física, UNAM. Journal of Nuclear Physics, Material Sciences, Radiation and Applications, 6(1), 57-60. https://doi.org/10.15415/jnp.2018.61009
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Articles