Electron-Impact Ionization of Heavy Atoms Using the Time-Dependent Close-Coupling Method

The time-dependent close-coupling method has been recently applied to calculate electron-impact direct ionization cross sections for the Kr, W, and Pb atoms. An overview is presented for these three heavy neutral atom systems. When the direct ionization cross sections are combined with excitation-autoionization cross sections, the total ionization cross sections were found to be in reasonable agreement with crossed-beams measurements for Kr and Pb.

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Electron-impact ionization of the Pb atom

The European Physical Journal D ◽

10.1140/epjd/s10053-021-00043-5 ◽

2021 ◽

Vol 75 (2) ◽

Author(s):

M. S. Pindzola ◽

S. D. Loch ◽

J. P. Colgan

Keyword(s):

Electron Impact ◽

Cross Sections ◽

Impact Ionization ◽

Polarization Potential ◽

Time Dependent ◽

Experimental Measurements ◽

Ionization Cross ◽

Close Coupling ◽

Direct Ionization ◽

Ionization Cross Sections

Abstract Electron-impact ionization cross sections are calculated for the ground configuration of the Pb atom. Time-dependent close-coupling cross sections for the direct ionization of the 6s and 6p subshells leading to single ionization are calculated with and without a polarization potential. Configuration-average distorted-wave cross sections for the direct ionization of the 6s and 6p subshells leading to single ionization are also calculated with and without a polarization potential. We find the time-dependent close-coupling cross sections using a polarization potential to be in good agreement with convergent-close-coupling cross sections using a polarization potential. The total direct ionization cross sections are compared to two sets of experimental measurements. The differences between the direct ionization cross sections and the experimental measurements are mainly due to indirect ionization cross sections coming from the $$6s^2 6p^2 \rightarrow 6s 6p^3$$ 6 s 2 6 p 2 → 6 s 6 p 3 excitation followed by autoionization. GraphicAbstract

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Calculation of electron-impact excitation and ionization of atoms and ions

Canadian Journal of Physics ◽

10.1139/p96-802 ◽

1996 ◽

Vol 74 (11-12) ◽

pp. 875-882 ◽

Cited By ~ 8

Author(s):

Igor Bray

Keyword(s):

Electron Impact ◽

Cross Sections ◽

Coupling Method ◽

Impact Excitation ◽

Electron Impact Excitation ◽

Ionization Cross ◽

Close Coupling ◽

Spin Asymmetries ◽

Total Ionization ◽

Ionization Cross Sections

We present a review of applications of the convergent close-coupling method concentrating on spin-dependent electron-impact total ionization cross sections. The results for the electron-impact total ionization cross sections and the associated spin asymmetries of H, Li, O5+, Na, and He(23S) are reviewed, with new calculations being presented for the potassium target.

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

Atoms ◽

10.3390/atoms7030060 ◽

2019 ◽

Vol 7 (3) ◽

pp. 60 ◽

Cited By ~ 2

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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Direct Ionization Cross Sections of Uranium Atom By Electron Impact

Journal of Mountain Research ◽

10.51220/jmr.v16i2.19 ◽

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.

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Electron Impact Ionization of Inert Gases

Canadian Journal of Physics ◽

10.1139/p74-232 ◽

1974 ◽

Vol 52 (18) ◽

pp. 1755-1758 ◽

Cited By ~ 5

Author(s):

S. P. Khare ◽

B. D. Padalia ◽

R. M. Nayak

Keyword(s):

Experimental Data ◽

Electron Impact ◽

Cross Sections ◽

Impact Energy ◽

Impact Ionization ◽

Electron Impact Ionization ◽

Inert Gases ◽

Ionization Cross ◽

Total Ionization ◽

Ionization Cross Sections

Electron impact total ionization cross sections of neon, argon, krypton, and xenon have been calculated for the electron impact energy varying from threshold to 20 keV. The method of Khare and Padalia, modified to include approximately the effect of multi-ionization, has been employed. The results are in fair agreement with the experimental data.

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