TOTAL CROSS SECTIONS FOR IONIZATION BY ELECTRON IMPACT

1966 ◽  
Vol 44 (16) ◽  
pp. 1967-1973 ◽  
Author(s):  
A. G. Harrison ◽  
E. G. Jones ◽  
S. K. Gupta ◽  
G. P. Nagy
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Linear Correlation ◽  
Molecular Polarizability ◽  
Ionization Cross ◽  
Total Cross Sections ◽  
Atomic Ionization ◽  
Wide Range ◽  
The Cross ◽  
Ionization Cross Sections

Total cross sections for ionization by 75 V electrons have been measured for a wide range of molecules. On the whole the results are in agreement with the cross sections reported by Lampe etal. rather than those reported by Otvos and Stevenson. The results fit neither a single linear correlation with molecular polarizability nor a simple postulate of additivity of atomic ionization cross sections.

scholarly journals Direct Ionization Cross Sections of Uranium Atom By Electron Impact

2021 ◽  
Vol 16 (2) ◽  
Author(s):  
Shivani Gupta ◽  
Piyush Sinha
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Impact Ionization ◽  
Uranium Atom ◽  
Electron Impact Ionization ◽  
Ionization Cross ◽  
Direct Ionization ◽  
Wide Range ◽  
Ionization Cross Sections ◽  
Theoretical Results

A theoretical model for electron impact ionization cross section has been found to be reliable for wide range of atoms is applied in this paper to the Uranium atom. A modified Kim binary encounter Bethe (BEB) method and modified Khare BEB method is employed for calculating electron impact ionization cross sections. The present results so obtained are compared with experimental as well as theoretical results known to the best of our knowledge.

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.

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