Semiempirical Approximation to Cross Sections forLX-ray Production by Proton Impact

Quantitative PIXE analyses of single fluid inclusions in quartz crystals with a 1.92-MeV tandetron

“…Parameters required for the quantification are size and depth of the fluid inclusion, size of bubble in the inclusion, quartz density (2.65 g/cm 3 ) and fluid density, major-element composition of the matrix and fluid, the stopping powers and ranges of protons in matter [24], the X-ray ionization and production cross sections [25,26], the X-ray absorption coefficients [27], the measured X-ray intensities and the detector sensitivity for each element. The sizes of the fluid inclusion and bubble were measured under a microscope.…”

Empirical K-shell ionization cross-sections of elements from 4Be to 92U by proton impact

“…This situation motivated the authors to perform fittings of the available experimental data with analytical functions. For the L-shell ionization cross-sections, several authors have tried to perform fittings of the available experimental data and thus some contributions have been reported in the literature [2][3][4][5][6][7][8]. For the K-shell ionization cross-sections, Paul and Obermann [9] were the first which introduced the term ''reference" cross-sections to describe semi-empirical cross-sections obtained by averaging all the relevant published experimental data at that time.…”

Hafnium to thorium M-shell X-ray production cross sections by proton impact

“…So, it is desirable to derive more reliable M X-ray production cross sections by using analytical formulas, which are based on the direct fitting of the experimental data (empirical cross section) and also on the fitting of the normalized experimental data to their corresponding theoretical values calculated within the ECPSSR model of Brandt and Lapicki (1981) (semi-empirical cross section). Several authors tried to perform the fittings of the available experimental data with analytical functions for both K (Paul, 1984) and L shell (Kahoul & Nekab, 2005;Miyagawa, Nakamura, & Miyagawa, 1988;Nekab & Kahoul, 2006;Orlic, 1994;Orlic, Sow, & Tang, 1994;Reis & Jesus, 1996;Sow, Orlic, Loh, & Tang, 1993;Strivay & Weber, 2002). More recently, Pajek et al (1999) and Jask oła et al (2000) presented their results, for protons and deuterons, respectively, for M shell in a universal way by plotting the measured M-shell X-ray production cross sections for M ab , M g and M 3 O 45 X-ray lines for different Zgroup as a function of the scaled velocity x M (empirical cross section).…”