Experimental investigation of photon mass attenuation coefficients in the ultra-soft energy rang
Résumé
Within the field of quantitative X-ray analysis techniques, such as electron probe microanalysis, precise knowledge of fundamental parameters holds great importance. In particular, the use of accurate photon mass attenuation coefficients is essential to perform correct elemental quantification [1]. While the widely used databases offer agreement for the hard X-ray range, significant differences arise for lower photon energies [2]. Moreover, tackling the uncertainties of the tabulated data, which may reach several hundred percent, is imperative [3]. Regarding recent advancement in analytical techniques for the low energy range including investigation of materials containing lithium, the interest in a reliable set of photon mass attenuation coefficients is steadily increasing.
In this study, we present experimental determination of photon mass attenuation coefficients for lithium fluoride (LiF), aluminium, and various transition metals in the extreme low energy range from 40 eV to a several hundreds of eV. The high-accuracy measurement allows a comparison with existing data tables and reveals significant differences, especially around the absorption edges. The novel dataset represents a valuable addition to the existing databases and its use may help to overcome current limitations in quantitative soft-X ray analysis.
[1] Bastin GF, Heijligers HJM, Quantitative electron probe microanalysis of ultralight elements (boron-oxygen). Scanning. 1990;12(4):225–36.
[2] Llovet X, Pöml P, Moy A, Fournelle JH. Assessing the Accuracy of Mass Attenuation Coefficients for Soft X-ray EPMA. Microsc Microanal. 2023 Apr;29(2):540–51.
[3] Cullen DE, Hubbell JH, Kissel L. EPDL97: the evaluated photo data library `97 version [Internet]. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); 1997 Sep, Available from: https://www.osti.gov/biblio/295438.