scholarly journals Cross sections for the electron impact non-dissociative ion of hydrogen and its isotopic molecule

2012 ◽  
Vol 61 (4) ◽  
pp. 043404
Author(s):  
He Man-Li ◽  
Wang Xiao ◽  
Gao Si-Feng
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Isotopic Molecule

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.

Integral cross sections for electron-impact excitation of the 33S and 31S states of He near threshold

2006 ◽  
Vol 39 (6) ◽  
pp. 1547-1561 ◽  
Author(s):  
M Stepanović ◽  
M Minić ◽  
D Cvejanović ◽  
J Jureta ◽  
J Kurepa ◽  
...  
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Impact Excitation ◽  
Electron Impact Excitation ◽  
Near Threshold

scholarly journals Calculation of Electron Impact Single Ionization TDCS of Tungsten Atoms at 200, 500 and 1000 eV

Atoms ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 31
Author(s):  
Ghanshyam Purohit
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Projectile Energy ◽  
Cross Section Data ◽  
Scattered Electron ◽  
Fusion Plasma ◽  
Magnetic Devices ◽  
Single Ionization ◽  
Section Data ◽  
Sensitive Dependence

We report triple differential cross-sections (TDCSs) for the electron impact single ionization of tungsten atoms for the ionization taking place from the outer sub shells of tungsten atoms, viz. W (6s), W (5d), W (5p) and W (4f). The study of the electron-induced processes such as ionization, excitation, autoionization from tungsten and its charged states is strongly required to diagnose and model the fusion plasma in magnetic devices such as Tokamaks. Particularly, the cross-section data are important to understand the electron spectroscopy involved in the fusion plasma. In the present study, we report TDCS results for the ionization of W atoms at 200, 500 and 1000 eV projectile energy at different values of scattered electron angles. It was observed that the trends of TDCSs for W (5d) are significantly different from the trends of TDCSs for W (6s), W (5p) and W (4f). It was further observed that the TDCS for W atoms has sensitive dependence on value of momentum transfer and projectile energy.

scholarly journals Few Body Effects in the Electron and Positron Impact Ionization of Atoms

Atoms ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 33
Author(s):  
R.I. Campeanu ◽  
Colm T. Whelan
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Differential Cross ◽  
Impact Ionization ◽  
Inert Gas ◽  
Interference Effects ◽  
Positron Impact ◽  
Competing Interactions ◽  
Energy Sharing

Triple differential cross sections (TDCS) are presented for the electron and positron impact ionization of inert gas atoms in a range of energy sharing geometries where a number of significant few body effects compete to define the shape of the TDCS. Using both positrons and electrons as projectiles has opened up the possibility of performing complementary studies which could effectively isolate competing interactions that cannot be separately detected in an experiment with a single projectile. Results will be presented in kinematics where the electron impact ionization appears to be well understood and using the same kinematics positron cross sections will be presented. The kinematics are then varied in order to focus on the role of distortion, post collision interaction (pci), and interference effects.

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