Total Ionization Cross Sections for Electron Scattering from Atomic and Molecular Targets Using Quantum Mechanical Semi-Empirical Approach from Threshold to 400 eV

2000 ◽  
pp. 121-132
Author(s):  
K. L. Baluja
Keyword(s):  
Electron Scattering ◽  
Cross Sections ◽  
Molecular Targets ◽  
Empirical Approach ◽  
Quantum Mechanical ◽  
Ionization Cross ◽  
Total Ionization ◽  
Ionization Cross Sections ◽  
Semi Empirical

Relative Variation of K- And L-Shell Ionization Cross Sections by Electron Impact

1999 ◽  
Vol 5 (S2) ◽  
pp. 584-585
Author(s):  
X. Llovet ◽  
C. Merlet ◽  
J.M. Fernández-Varea ◽  
F. Salvat
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Carbon Films ◽  
X Rays ◽  
Empirical Formulas ◽  
Relative Variation ◽  
Ionization Cross ◽  
Ionization Cross Sections ◽  
Semi Empirical ◽  
Shell Ionization

Knowledge of inner-shell ionization cross sections by electron impact is needed for quantitative procedures in electron probe microanalysis (EPMA) and Auger electron spectroscopy (AES) The common practice is to use semi-empirical formulas, based on the asymptotic limit of the Bethe theory, which sometimes are used beyond their domain of validity. Experimental measurements of ionization cross sections are scarce and affected by considerable uncertainties, thus a mere comparison with experimental data does not permit to draw a definite conclusion abou the accuracy of the various formulas. In this communication, we present new measurements o the relative variation of K- and L-shell ionization cross sections deduced from the counting rate of characteristic x-rays emitted by extremely thin films of Cr, Ni, Cu, Te, Au and Bi bombardec by keV electrons.The studied films were produced by thermal evaporation on backing self-supported 30 nm carbon films.

scholarly journals The Electron Impact Ionization Cross Sections of Methanol, Ethanol and 1-Propanol

Atoms ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 60 ◽  
Author(s):  
Yogesh Kumar ◽  
Manoj Kumar ◽  
Sachin Kumar ◽  
Rajeev Kumar
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Impact Ionization ◽  
Experimental Results ◽  
Oscillator Strengths ◽  
Ionization Cross ◽  
Total Ionization ◽  
Plane Wave Born Approximation ◽  
Ionization Cross Sections ◽  
Good Agreement

In the present investigation, the plane-wave Born approximation was employed to calculate the total ionization cross sections by electron impact of methanol, ethanol and 1-propanol from the threshold of ionization to 10 MeV. This method requires continuum generalized oscillator strengths (CGOSs). The two different semi-phenomenological expressions of CGOS, given by Mayol and Salvat and Weizsacker and Williams, along with approximated form of the continuum optical oscillator strength (COOS) by Khare et al. were used. Furthermore, the average of the above two CGOSs was also used. The calculated ionization cross sections were compared to the available previous theoretical results and experimental data. Out of three CGOSs, the present results with the average CGOS were found in good agreement with the available experimental results for all the considered molecules. Collision parameters CRP were also calculated from 0.1 to 100 MeV and the calculations were found to be in excellent agreement with the experimental results of Reike and Prepejchal.

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