K -Shell X-Ray Fluorescence Parameters of a Few Low Z Elements
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K-Shell X-Ray Fluorescence Parameters of a Few Low Z Elements1 L. F. M. Ananda,b, S. B. Gudennavara,*, S. G. Bubblya, and B. R. Kerurc a Department
of Physics and Electronics, Christ University, Bengaluru-560029, Karnataka, India b Department of Physics, Government First Grade College, K. R. Puram, Bengaluru-560036, Karnataka, India c Department of Physics, Gulbarga University, Kalaburgi-585106, Karnataka, India * e-mail: [email protected] Received May 9, 2017
Abstract—K-shell X-ray fluorescence parameters of low Z elements cobalt, nickel, copper, and zinc have been measured employing a simple method. These elemental targets were excited by using 32.86 keV barium K X-ray photons from a weak 137Cs γ-ray source, and the emitted K-shell X-rays from these targets were detected using a low-energy high-purity germanium X-ray detector spectrometer. The results are compared with the standard theoretical, semi-empirical, fitted values and with the others’ experimental values. DOI: 10.1134/S1063776118010016
1. INTRODUCTION X-ray fluorescence (XRF) technique has gained considerable interest as a tool for elemental analysis in various fields of science. Precise and reliable elemental quantifications require accurate values of XRF parameters such as shell-wise X-ray fluorescence cross-sections, X-ray fluorescence yields, ratio between the radiative transition width and radiationless (Auger) transition width, X-ray intensity ratios, vacancy transfer probabilities, jump ratios and jump factors. When an energetic X-ray/γ-ray interacts with an atom, an electron gets ejected from the inner shell of the atom leaving behind a vacancy in that shell. If an electron from a higher shell occupies the vacancy so created in the inner shell, the difference in the binding energies of the electron is emitted as characteristic X-ray. However, it is also possible that the difference in binding energies of the electron can be directly transferred to one of the electrons in a higher shell (say L-shell or M-shell) causing the electron in that shell to get ejected from the atom. The process is known as an Auger process, and the ejected electron is called an Auger electron. The emission of a fluorescence X-ray is referred to as a radiative transition, while the emission of an Auger electron is referred to as a radiationless transition or Auger transition. XRF studies involving single and double reflection geometries and strong radioactive sources of the order
of 109 Bq, have been reported by many researchers [1– 6]. A compilation of data based on the several experimental, theoretical, semi-empirical and fitted values has been published by Kahoul et al. [7] supporting the exhaustive XRF research work that has been in progress. Though these methods (single and double reflection geometries) give accurate XRF parameters, they are a bit complex and involve strong radioactive sources. However, a simple 2π-geometrical configuration method to measure K-shell X-ray fluorescence parameters was proposed earlier by o
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