Rıdvan Durak

Measurement of M shell X-ray production cross sections and fluorescence yields for the elements in the atomic range 70 ≤ Z ≤ 92 at 5.96 keV

Total M X-ray cross sections for 12 elements in atomic range 70 ≤ Z ≤ 92 were measured at 5.96 keV Mn K X-ray photon energy. The average M shell fluorescence yields (ωM of these elements have also been observed using the presently measured cross section values and the theoretical M shell photoionisation cross section values.

Studies on effective atomic numbers, electron densities from mass attenuation coefficients near the K edge in some samarium compounds

The effective atomic numbers and electron densities of some samarium compounds were determined using the experimental total mass attenuation coefficient values near the K edge in the X-ray energy range from 36.847 up to 57.142 keV. The measurements, in the region from 36.847 to 57.142 keV, were done in a transmission geometry utilizing the Kα2, Kα1, Kβ1 and Kβ2 X-rays from different secondary source targets excited by the 59.54 keV gamma-photons from an Am-241 annular source. This paper presents the first measurement of the effective atomic numbers and electron densities for some samarium compounds near the K edge. The results of the study showed that the measured values were in good agreement with the theoretically calculated ones.

Photon-induced M-shell X-ray production cross-sections and fluorescence yields in heavy elements at 5.96 keV

Abstract Total M-shell X-ray production cross-sections (MXRP) for selected heavy elements between Yb and U at have been measured at 5.96 keV incident photon energy using a Si(Li) detector. The average M-shell fluorescence yields have been derived, using the experimental total M X-ray production cross-sections and theoretical M-shell photoionization cross-sections. Extracted cross-sections and fluorescence yields have been compared with the literature experimental values, theoretical predictions and semiempirical fits.

L, Lα, Lβ and Lγ X-ray production cross-sections and yields of some selected elements between caesium and erbium following ionization by 59.54 keV γ rays

Abstract L l , Lα, Lβ and Lγ X-ray production cross-sections were measured in elements from Cs to Er following ionization for 59.54 keV γ-rays from an 241Am point source. The measured values are compared with theoretical predictions estimated using subshell photoionization cross-sections, fluorescence yields, Coster–Kronig transition probabilities, K to Li subshell vacancy transfer probabilities and radiative decay rates. Average L-shell fluorescence yields were deduced from present measured total L X-ray production cross-sections, theoretical K and L photoionization cross-sections and K to L vacancy transfer probabilities. The obtained results for L X-ray production cross-sections and average L-shell fluorescence yields are compared with recent experimental values, theoretical predictions, and semiempirical fits.

L-shell polarization and alignment of heavy elements induced by 59.54 keV photons

The polarization (%) of L-shell fluorescent X-rays (Lα, Lβ and Ll) of Lu, Hf, Ta, W, Os, Pt, Au, Hg, Tl, Pb, Bi, Th and U excited by 59.54keV photons has been measured. These polarization degrees were then used to determine the alignment parameters A(2.) The Ll X-rays were found to be strongly polarized, whereas Lα and Lβ X-rays showed less polarization. In this regard, the Lα, Lβ and Ll groups show anisotropic spatial distributions. The results for polarization (%) as well as alignment parameters were compared with the ones available in literature.

L-subshell fluorescence yields (ω1, ω2 and ω3) for elements in the atomic range 55 ≤ Z ≤ 68 with a Si(Li) detector

Abstract Lα, Lβ and Lγ X-ray production cross-sections of 55 Cs , 56 Ba , 57 La , 58 Ce , 59 Pr , 60 Nd , 62 Sm , 65 Tb , 66 Dy , 67 Ho and 68 Er have been measured by using a Si(Li) detector coupled to a model 1024 computerized multi-channel analyzer. The L-subshell X-ray fluorescence yields ω1, ω2 and ω3 have been derived, using the experimental Lα, Lβ and Lγ X-ray production cross-sections, theoretical L-subshell photoionization cross-sections, Coster-Kronig transition probabilities, vacancy transfer probabilities and fractional X-ray emission rates. The experimental data have been compared with the literature experimental data, theoretical predictions based on Dirac–Hartree–Slater wave functions and semiempirical compilations.

Measurement of photon-induced L X-ray production cross-sections for some elements with 40 ≤ Z ≤ 70 at 122 keV

Abstract X-ray production cross-sections for Kα and Kβ X-ray line were measured for Zr, Mo, Ag, In, Sn, Ba, Ce, Nd, Gd, Dy, Er and Yb at a photon excitation energy of 122 keV using a high-resolution Ge(Li)detector. Experimental results were compared with the theoretical values using Kβ/Kα intensity ratios based on Hartree-Fock and Hartree-Slater theories. The results were in good agreement the theoretical values.

K- to L- and M-shell radiative vacancy transfer probability measurements in some elements from Nd to Pb

Radiative vacancy transfer probabilities from K-shell to -subshell and M-shell were deduced for the elements Nd, Sm, Eu, Gd, Dy, Ho, Er, Yb, Ta, W, Hg and Pb by measuring characteristic K x-rays from targets excited by 123.6 keV photons. Comparisons between present experimental results and theoretical predictions were made.

Determination of L X-ray fluorescence parameters for Ho, Lu, W, Hg and Bi.

In this work, L X-ray fluorescence cross sections, L sub-shell fluorescence yields and level widths and radiative vacancy transfer probabilities of L sub-shells to Mi, Ni and Oi sub-shells were measured for the elements Ho, Lu, W, Hg and Bi. Energy dispersive X-ray fluorescence (EDXRF) technique was used to measure L X-ray photons. To obtain related parameters, we used 59.54 keV gamma photons of (241)Am radioactive point source. Emitted L X-ray photons from targets were collected by means of a Si(Li) detector with resolution of 180 eV at 5.9 keV. The present results are generally in a good agreement with theoretical calculations and the other results obtained in the literature, within their range considering experimental uncertainty.

Qualitative and quantitative analysis of pathological and non-pathological human bone using radioisotope X-ray fluorescence technique

Abstract Pathological and non-pathological human elbow bone samples were collected from one male human patient and one female human patient who were undergoing treatment in our University Research Hospital. Pathological and non-pathological human elbow bone samples were analyzed by means of energy-dispersive X-ray fluorescence spectrometry by using standard additions method. Experimental results are presented and discussed in this work.