Geant4 x-ray fluorescence with updated libraries

We present the results concerning the development in Geant4 of a new data driven library, called here the ANSTO HF library. This X-ray fluorescence library is based on an approach of particular interest for PIXE simulation applications; however, it can be used in any Geant4 applications where X-ray fluorescence needs to be described. The X-ray fluorescence transition probabilities were calculated within the Hartree-Fock (HF) approach, which is recognised to better reproduce PIXE experimental values compared with the Hartree-Slater approach, adopted in the current default Geant4 EADL data library. These HF X-ray fluorescence transition probabilities were integrated into a new Geant4 library and will be released within Geant4 in the near future. In this paper, we compare the fluorescence X-ray spectra generated by the ANSTO HF library and by the currently available library (EADL-1991 [1]) within Geant4, for targets irradiated with protons and α particles with energies up to 10 MeV, a range of interest for PIXE applications. The comparisons were performed for a large set of sample materials spanning a broad range of target atomic numbers. These two approaches were compared to existing experimental measurements performed at the ANSTO heavy ion microprobe beamline using 2 MeV and 3 MeV proton and 10 MeV He2+ ion beams. This work represents a useful upgrade to the Geant4 atomic de-excitation package. © 2021 Elsevier B.V.

Keywords

PIXE analysis, Cross sections, X-ray fluorescence analysis, ANSTO, Simulation, Hartree-Fock method, Spectra, Heavy ion beam probe

Citation

Bakr, S., Cohen, D. D., Siegele, R., Archer, J. W., Incerti, S., Ivanchenko, V., Mantero, A., Rosenfeld, A., & Guatelli, S. (2021). Geant4 x-ray fluorescence with updated libraries. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 507, 11-19. doi:10.1016/j.nimb.2021.09.009