Omer Sogut

Chemical effects on Kβ/Kα X-ray intensity ratios of Mo, Ag, Cd, Ba, La, Ce compounds and total mass attenuation coefficients of Fe and Cu

Abstract The Kβ/Kα intensity ratios for pure Mo, Ag, Cd, Ba, La and Ce elements and for some of their compounds were investigated. The vacancies in the K shell were created by 59.5-keV γ-rays from a heavily filtered 241 Am radioactive source. K X-rays were measured using a Si(Li) detector with a resolution of 155 eV at 5.9 keV. We observed chemical effects on Kβ/Kα intensity ratios of Mo, Ag, Cd, Ba, La and Ce compounds. Detailed interpretation of data obtained from X-ray transmission measurements usually depends on the assumption that the contribution of each element is additive. This assumption yields the mixture rule for X-ray attenuation coefficients which is valid if molecular and chemical effects are negligible. We measured the total mass attenuation coefficients of Fe and Cu in various compounds. Self-absorption corrections were carried out on data for ligands in the different compounds. Our values were compared with the theoretical values for pure elements.

Alloying Effect on Kβ/Kα Intensity Ratios in CrxNi1−x and CrxAl1−x Alloys

Introduction The Kα X-rays and the Kβ X-rays are two main components of the K X-ray emission lines of an atom when its K shell electrons are ejected by γ-rays or other energetic particles. A precise measurement of the Kβ/Kα intensity ratios is of great interest for quantitative analysis of trace elements; this is important because by comparison with the relevant theoretical values based on atomic models, there is the possibility to test the validity of the models.

Measurement of the Kα and Kβ X-rays polarization degree and polarization effect on the Kβ/Kα intensity ratio

Abstract The linear polarization degree of K α and K β X-rays of some elements in the atomic range 57⩽ Z ⩽69 has been measured. In addition, the polarization effect on the intensity ratio of these elements is investigated. It is found that the K β X-rays are more polarized than K α X-rays. The polarization effect on the K β /K α intensity ratio was investigated. Because the polarization of characteristic K X-ray is not found in the literature the comparison was not made with other experimental and theoretical results.

Chemical Effect on L X-ray Intensity Ratios of Mercury, Lead, and Bismuth

INTRODUCTION The information regarding the experimental values of K and L X-ray intensity ratios are important due to its wide use in many areas of basic and applied science and non-destructive elemental analysis of materials using the X-ray fluorescence technique. Chemical effects on K and L X-ray intensity ratios are not very well known, but they are an interesting subject. Some studies [1–4] addressing chemical effects on the Kβ/Kα intensity ratios have been made. We investigated chemical effects [5–7] and alloying effects [8] on the Kβ/Kα intensity ratios, and measured Kβ/Kα intensity ratios following radioactive decay and photoionisation [9]. But there are few studies addressing chemical effects on the L X-rays intensity ratios. Iihara et a1.[10] examined chemical effects on chromium L X-rays.

Measurement of angular dependence of photon-induced differential cross-sections of M X-rays from Pt, Au and Hg at 5.96 keV

Abstract The differential cross-section for the emission of M shell fluorescence X-rays from Pt, Au and Hg by 5.96 keV photons at seven angles ranging from 50° to 110° have been measured. The differential cross-section is found to decrease with increase in the emission angle, showing an anisotropic spatial distribution of M shell fluorescence X-rays. The present results contradict the predictions of Cooper and Zare (Cooper, J., Zare, R.N., 1969. Atomic Collisions Processes, vol. XIC. Gordon and Breach, New York. p.317) that after photoionization of inner shells, the vacancy state has equal population of magnetic substates and that the subsequent X-ray emission is isotropic, but confirm the predictions of the calculations of Flugge, Mehlhorn and Schmidt that the atomic inner-shell vacancies produced after photoionization are aligned and X-ray emission from the filling of vacancies in states with J >1/2 is anisotropic. The vacancies were created by the 5.96 keV γ-rays from an 55 Fe source and the M X-rays were measured using a Si(Li) detector.

Variation of K X-ray fluorescence cross-sections of Fe in F compounds at an energy interval of 7.6–14.4 keV

Abstract The photon-induced K X-ray fluorescence cross-sections (σ K α , σ K β ) for Fe in F compounds were investigated. Measurements were carried out at 10 different energies in the interval of 7.6–14.4 keV by using a secondary excitation method. K X-rays emitted by samples were counted by a Si(Li) detector with a resolution of 160 eV at 5.9 keV. Obtained values were compared with the theoretical values of pure elements.

Chemical effect on total mass attenuation coefficients of V, Cr, Mn, Co and Ni

Detailed interpretation of data obtained from X-ray transmission measurements usually depends on the assumption that the contribution of each element is additive. This assumption yields the mixture rule for X-ray attenuation coefficients which is valid if molecular and chemical effects are negligible. We measured the total mass attenuation coefficients of V, Cr, Mn, Co and Ni in various their compounds. Absorption corrections were carried on data for ligands in the compounds. We found that V, Cr, Mn, Co and Ni have different total mass attenuation coefficients in the different compounds. We compared our results with theoretical values of Hubbell and Seltzer.

L X-ray intensity ratios of some elements in the region of 56≤Z≤83

L X-ray intensity ratios of Ba, La, Ce, Gd, Er, Yb, Ta, Au, Hg, Pb, Bi have been measured. The L shell elctrons are excited by 59.5 keV gamma-rays from 241 Am and the L X-rays from samples are measured with a Si(Li) detector. The experimental values are compared with the theoretical values of the pure elements.

Measurement of K-shell fluorescence yields for Br and I compounds using radioisotope XRF

Abstract K fluorescence yields were measured for I and Br compounds. The samples were excited by γ-rays 59.5 keV produced by a Am-241 radioisotope source. The K X-rays emitted by the samples were counted using a Si(Li) detector with a resolution of 155 eV at 5.9 keV . Experimental results were compared with the theoretical values of Br and I elements.

Chemical effects on L shell fluorescence yields of Ba, La and Ce compounds

Chemical effects on the average L shell fluorescence yields (vL) for Ba, La and Ce compounds were investigated. Samples were excited by gamma-rays with 59.5 keV energy photons from a 241Am radioisotope source. L X-rays emitted by samples were counted by a Si(Li) detector with a resolution 155 eV at 5.9 keV. Chemical effects on the average L shell fluorescence yield (vL) for Ba, La and Ce compounds were observed. The values are compared with theoretical and experimental ones for the pure elements.