Measurements of mass attenuation coefficients and determination of photoionization cross sections at energies across the Li (i=1–3) edges of 66Dy. (July 2017)

• Record Type: Journal Article
• Authors: Kaur, Rajnish; Kumar, Anil; Osan, Janos; Czyzycki, M.; Karydas, A.G.; Puri, Sanjiv
• Is Part Of: Radiation physics and chemistry. Volume 136(2017)
• Page Start: 30
• Page End: 37
• Publication Date: 2017-07
• Subjects: Mass attenuation coefficients -- Photoionization cross sections -- Synchrotron radiation -- Absorption edge jump ratio; Radiation chemistry -- Periodicals; Radiometry -- Periodicals; Radiation -- Periodicals; Chimie sous rayonnement -- Périodiques; 539.2
• DOI: 10.1016/j.radphyschem.2017.03.028
• Languages: English
• ISSNs: 0969-806X

Abstract

Abstract: The absolute values of the mass attenuation coefficients have been measured at sixty two photon energies across the Li (i=1–3) sub-shell absorption edges of66 Dy covering the region 7.6–14.0 keV in order to investigate the influence of near-edge processes on the attenuation coefficients. The present measured attenuation coefficients are found to be higher by up to 10% than the theoretical values evaluated from the computer code XCOM (Berger et al., 2010 ) and the self-consistent Dirac-Hartree-Slater (DHS) model based values tabulated byChantler (1995) over the energy region 7.6–14.0 keV, except at energies in vicinity (few eV) of the Li (i=1–3) sub-shell absorption edge energies where the measured values are significantly higher (up to 37%) than both the sets of theoretical values. Further, the Li (i=1–3) sub-shell photoionization cross sections, ( σ Li P ) exp, deduced from the present measured mass attenuation coefficients are compared with the non-relativistic Hartree-Fock-Slater (HFS) model based values tabulated byScofield (1973) and those evaluated from the theoretical total photoionization attenuation coefficients tabulated byChantler (1995) . The deduced ( σ Li P ) exp (i=1–3) values are found to be in better agreement with those evaluated from the tabulations given byChantler (1995) than the values given byScofield (1973) over the energy region 7.8 – 14.0 keV included in this study. However, at photon energies up to few eV above the Li edges, the deduced ( σ Li P ) exp (i=1–3) values are found to be significantly higher (up to 32%) than both the sets of theoretical values. Highlights: Absolute mass attenuation coefficients measured at photon energies across the Li (i=1–3) edges of66 Dy. The measured values compared with those obtained from XCOM and the DHS model based values. Li (i=1–3) subshell photoionization cross sections for66 Dy deduced from measured mass attenuation coefficients.