K-Shell Ionization by Light Ions: Comparison between Published Cross Sections and Theories

1981 ◽  
pp. 13-16
Author(s):  
Helmut Paul
Keyword(s):  
Cross Sections ◽  
Light Ions ◽  
Shell Ionization

Review of experimental cross sections for K-shell ionization by light ions

1986 ◽  
Vol 135 (2) ◽  
pp. 47-97 ◽  
Author(s):  
Helmut Paul ◽  
Johannes Muhr
Keyword(s):  
Cross Sections ◽  
Experimental Cross ◽  
Light Ions ◽  
Shell Ionization

SIGMAL: A Program for Calculating L-Shell lonization Cross-Sections

1981 ◽  
Vol 39 ◽  
pp. 198-199 ◽  
Author(s):  
R.F. Egerton
Keyword(s):  
Cross Sections ◽  
Fortran Program ◽  
Absorption Data ◽  
X Ray ◽  
Atomic Electrons ◽  
Energy Dependent ◽  
Hydrogenic Model ◽  
Electron Energy Loss ◽  
X Ray Absorption ◽  
Shell Ionization

SIGMAL is a short (∼ 100-line) Fortran program designed to rapidly compute cross-sections for L-shell ionization, particularly the partial crosssections required in quantitative electron energy-loss microanalysis. The program is based on a hydrogenic model, the L1 and L23 subshells being represented by scaled Coulombic wave functions, which allows the generalized oscillator strength (GOS) to be expressed analytically. In this basic form, the model predicts too large a cross-section at energies near to the ionization edge (see Fig. 1), due mainly to the fact that the screening effect of the atomic electrons is assumed constant over the L-shell region. This can be remedied by applying an energy-dependent correction to the GOS or to the effective nuclear charge, resulting in much closer agreement with experimental X-ray absorption data and with more sophisticated calculations (see Fig. 1 ).

The measurement of inner-shell ionization cross aections by electron impact in a TEM

1992 ◽  
Vol 50 (2) ◽  
pp. 1266-1267
Author(s):  
Raynald Gauvin ◽  
Gilles L'Espérance
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Weight Fraction ◽  
Thin Foil ◽  
Specimen Thickness ◽  
Ionization Cross ◽  
Electron Dose ◽  
Total Electron ◽  
Inner Shell Ionization ◽  
Shell Ionization

Values of cross sections for ionization of inner-shell electrons by electron impact are required for electron probe microanalysis, Auger-electron spectroscopy and electron energy-loss spectroscopy. In this work, the results of the measurement of inner-shell ionization cross-sections by electron impact, Q, in a TEM are presented for the K shell.The measurement of QNi has been performed at 120 KeV in a TEM by measuring the net X-ray intensity of the Kα line of Ni, INi, which is related to QNi by the relation :(1)where i is the total electron dose, (Ω/4π)is the fractional solid angle, ω is the fluorescence yield, α is the relative intensity factor, ε is the Si (Li) detector efficiency, A is the atomic weight, ρ is the sample density, No is Avogadro's number, t' is the distance traveled by the electrons in the specimen which is equal to τ sec θ neglecting beam broadening where τ is the specimen thickness and θ is the angle between the electron beam and the normal of the thin foil and CNi is the weight fraction of Ni.

ENERGY-LOSS EFFECT IN K-SHELL IONIZATION

1998 ◽  
Vol 08 (04) ◽  
pp. 225-233 ◽  
Author(s):  
TAKESHI MUKOYAMA
Keyword(s):  
Energy Loss ◽  
Cross Sections ◽  
Relativistic Correction ◽  
Correction Method ◽  
Exact Integration ◽  
Plane Wave Born Approximation ◽  
Ionization Cross Sections ◽  
Energy And Momentum ◽  
Shell Ionization ◽  
Loss Effect

The energy-loss effect of the projectile for direct inner-shell ionization cross sections by charged-particle impact has been examined. The relativistic and nonrelativistic calculations for K-shell ionization with and without the energy-loss effect are made in the plane-wave Born approximation and compared with the Brandt-Lapicki theory for the corrections of the relativistic and energy-loss effect. It is demonstrated that the Brandt-Lapicki method gives a good approximation to both relativistic and nonrelativistic cross sections, which implicitly take into account the energy-loss effect. However, the use of the Brandt-Lapicki relativistic correction method in the nonrelativistic theory with the exact integration limits for energy and momentum transfer overestimates the relativistic calculations for low-energy projectiles. This indicates that the Brandt-Lapicki method for correction of the electronic relativistic effect should be used only with their energy-loss correction method.

Measurement and Multiple Scattering Correction of K-Shell Ionization Cross Sections of Silver by Electron Impact

2001 ◽  
Vol 18 (4) ◽  
pp. 531-532 ◽  
Author(s):  
Zhou Chang-Geng ◽  
Fu Yu-Chuan ◽  
An Zhu ◽  
Tang Chang-Huan ◽  
Luo Zheng-Ming
Keyword(s):  
Electron Impact ◽  
Multiple Scattering ◽  
Cross Sections ◽  
Ionization Cross ◽  
Scattering Correction ◽  
Ionization Cross Sections ◽  
Shell Ionization

scholarly journals Ion-induced ionization and capture cross sections for DNA nucleobases impacted by light ions

2012 ◽  
Vol 388 (10) ◽  
pp. 102004
Author(s):  
Christophe Champion ◽  
Mariel E Galassi ◽  
Philippe F Weck ◽  
Omar Fojón ◽  
Jocelyn Hanssen ◽  
...  
Keyword(s):  
Cross Sections ◽  
Capture Cross ◽  
Light Ions ◽  
Dna Nucleobases ◽  
Capture Cross Sections
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