کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5426998 | 1508611 | 2018 | 10 صفحه PDF | دانلود رایگان |
- First time M sub-shell emission cross-section measurements at 5, 7 & 9â¯keV photons.
- Comparison with theoretical evaluations from different model data for atomic parameters.
- Measurements support the relativistic DF theory.
- Explained deviations between measured and theoretical cross-sections with trends of the parameters with Z.
- Spots of deviations almost coincide with crisscross/sharp variation in physical parameter trends.
M sub-shell X-ray fluorescence cross-sections of elements Pt, Au, Hg, Pb, Th and U have been measured with linearly polarized photon beams from Indus-II synchrotron source at Raja Ramanna Centre for Advanced Technology (RRCAT), India at tuned 5, 7 and 9â¯keV energies less than the L3 edge energy of elements. Measurements at present energies and elements are not available in literature. Therefore, measured cross-sections for Mξ, Mδ, Mα, Mβ, Mγ, Mm1 and Mm2 group of X-rays were compared with calculated theoretical values based upon Non Relativistic Hartree-Slater (NRHS) and relativistic Dirac-Fork (DF) and Dirac-Hartree-Slater (DHS) models. The measured cross-sections along with our earlier quoted measurements at 8 and 10â¯keV by Kaur et al. [Nucl. Instrum. Meth. B, 2014; 320: 37] are found in good agreement with DF and DHS values around 20% deviations and are highly deviated from NRHS values. Most of the spots of observed high deviations in measured and theoretical cross-sections are found to coincide with the presence of crisscrosses/sharp variations in contributing physical parameters photo-ionization cross-sections ÏMi's and Coster-Kronig yields fij's with Zs.
Journal: Journal of Quantitative Spectroscopy and Radiative Transfer - Volume 204, January 2018, Pages 232-241