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Determination of atomic fundamental parameters

Brief description of the Method

Fundamental parameter based quantitative X-Ray fluorescence analysis relies on an exact knowledge of the atomic fundamental parameters. This includes for example the different absortion cross sections, fluorescence yields or Coster-Kronig transition probabilities. Available FP-databases for PCS data and other FP’s, e.g. Coster-Kronig transition probabilities or fluorescence yields are of very diverse quality.

Using PTB’s reference free XRF instrumentation [1], atomic fundamental parameters can be experimentally determined with known experimental uncertainties. Elements from boron [2] up to lead [3] and higher are available for FP determinations.

Expertise

  • Well-characterized intrumentation with calibrated diaphragms
  • Absolutely calibrated detectors
  • Multiplett fitting [3]

Applications

  • Fluorescence yields
  • Coster-Kronig yields
  • Photoionization yields
  • Transition Probabilities

Specifications

  • Excitation between 78 eV and 60 keV available
  • Calibrated silicon drift detectors (SDD) with known response functions
  • Various calibrated photo diodes to determine incident photon flux

Research Highlights

  • Light element [1] and other FP determinations [2]
  • Determination of resonant Raman scattering cross sections [3]
  • Experimental validation of L-subshell photoionization cross sections [4]

References

  1. Determination of fluorescence yields using monochromized undulator radiation of high spectral purity and well known flux, Adv. X-Ray Anal. (2001) 44, 349-354
  2. Opens external link in new windowL-subshell fluorescence yields and Coster-Kronig transition probabilities with a reliable uncertainty budget for selected high- and medium-Z elements, Phys. Rev. A 86, 042512 (2012)
  3. Opens external link in new windowNi LIII fluorescence and satellite transition probabilities determined with an alternative methodology for soft-x-ray emission spectrometry, Phys. Rev. A74 (2006) 74, 012702
  4. Opens external link in new windowExperimental verification of the individual energy dependencies of the partial L-shell photoionization cross sections of Pd and Mo, Phys. Rev. Lett. (2014) 113(16), 163001