Charge transfer from rare gas atoms to Kr+

1982 ◽  
Vol 60 (7) ◽  
pp. 981-987 ◽  
Author(s):  
B. Hird ◽  
S. P. Ali
Keyword(s):  
Charge Transfer ◽  
Energy Dependence ◽  
Cross Section ◽  
Rare Gas ◽  
Zener Model ◽  
Energy Data ◽  
Model Predictions ◽  
Rare Gas Atoms ◽  
The Cross ◽  
Good Agreement

The cross section for electron capture by Kr+ ions from rare gas atoms between 30 and 120 keV is found to be in good agreement with previous measurements where these exist, except for neon. The Rapp–Francis model gives an acceptable fit to the energy dependence of these and higher energy data but is too large by a factor of about five. In contrast the Landau–Zener model predictions are too large for helium and neon and too small for the heavier targets unless metastable states of krypton with large polarizabilities dominate the cross section.

Electron loss cross sections from rare gas atoms to Ar+

1982 ◽  
Vol 60 (7) ◽  
pp. 977-980
Author(s):  
B. Hird ◽  
S. P. Ali
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Energy Region ◽  
Rare Gas ◽  
Electron Loss ◽  
Rare Gases ◽  
Thin Target ◽  
Rare Gas Atoms ◽  
Good Agreement

Measurements of the σ10 cross section for a beam of Ar+ ions of energies between 30 and 120 keV passing through a thin target of the rare gases show good agreement with the few previous measurements in this energy region.

On the validity of the approximations used in asymmetric charge transfer collision calculations

1981 ◽  
Vol 59 (4) ◽  
pp. 576-584 ◽  
Author(s):  
B. Hird ◽  
S. P. Ali
Keyword(s):  
Electron Transfer ◽  
Wave Function ◽  
Charge Transfer ◽  
Alkali Metal ◽  
Energy Dependence ◽  
Cross Section ◽  
Transfer Process ◽  
Numerical Approximations ◽  
N Value ◽  
Good Agreement

Some formalisms which have frequently been used in general noncrossing electron transfer theories are examined and shown to be analytically equivalent. The accuracy of the numerical approximations is found to be surprisingly good, partly because different approximations tend to have opposite effects. The hydrogenic wave function assumption of the Rapp and Francis theory is found to be seriously inadequate and the theory is generalized to Coulomb wavefunctions of higher n value. When these wavefunctions are suitably normalized the magnitude and overall energy dependence of the cross section is in good agreement with experiment in alkali metal collisions where this type of collision is expected to be the dominant transfer process.

scholarly journals Thermal conductivity of sandstones from Biot’s coefficient

Geophysics ◽  
2018 ◽  
Vol 83 (5) ◽  
pp. D173-D185 ◽  
Author(s):  
Tobias Orlander ◽  
Eirini Adamopoulou ◽  
Janus Jerver Asmussen ◽  
Adam Andrzej Marczyński ◽  
Harald Milsch ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Heat Flow ◽  
Cross Section ◽  
Geometric Mean ◽  
Well Log ◽  
Biot’S Coefficient ◽  
Model Predictions ◽  
The Cross ◽  
Rock Texture

Thermal conductivity of rocks is typically measured on core samples and cannot be directly measured from logs. We have developed a method to estimate thermal conductivity from logging data, where the key parameter is rock elasticity. This will be relevant for the subsurface industry. Present models for thermal conductivity are typically based primarily on porosity and are limited by inherent constraints and inadequate characterization of the rock texture and can therefore be inaccurate. Provided known or estimated mineralogy, we have developed a theoretical model for prediction of thermal conductivity with application to sandstones. Input parameters are derived from standard logging campaigns through conventional log interpretation. The model is formulated from a simplified rock cube enclosed in a unit volume, where a 1D heat flow passes through constituents in three parallel heat paths: solid, fluid, and solid-fluid in series. The cross section of each path perpendicular to the heat flow represents the rock texture: (1) The cross section with heat transfer through the solid alone is limited by grain contacts, and it is equal to the area governing the material stiffness and quantified through Biot’s coefficient. (2) The cross section with heat transfer through the fluid alone is equal to the area governing fluid flow in the same direction and quantified by a factor analogous to Kozeny’s factor for permeability. (3) The residual cross section involves the residual constituents in the solid-fluid heat path. By using laboratory data for outcrop sandstones and well-log data from a Triassic sandstone formation in Denmark, we compared measured thermal conductivity with our model predictions as well as to the more conventional porosity-based geometric mean. For outcrop material, we find good agreement with model predictions from our work and with the geometric mean, whereas when using well-log data, our model predictions indicate better agreement.

Measurement of the translational energy dependence of the cross section for the reaction of Sr+CH3I→SrI+CH3 from 0.1 – 1.0 eV

1991 ◽  
Vol 176 (6) ◽  
pp. 499-503 ◽  
Author(s):  
Qi-Xun Xu ◽  
R. Scott Mackay ◽  
F.J. Aoiz ◽  
Mark A. Quesada ◽  
Patrick J. Grunberg ◽  
...  
Keyword(s):  
Energy Dependence ◽  
Cross Section ◽  
Translational Energy ◽  
The Cross

The inner shell ionization of atoms by electron impact

1940 ◽  
Vol 36 (1) ◽  
pp. 43-52 ◽  
Author(s):  
E. H. S. Burhop ◽  
H. S. W. Massey
Keyword(s):  
Experimental Data ◽  
Electron Impact ◽  
Cross Section ◽  
Nickel Silver ◽  
Inner Shell Ionization ◽  
Good For ◽  
The Cross ◽  
Shell Ionization ◽  
Good Agreement

Calculations have been made of the cross-section for ionization of the inner shells of atoms by electron impact in the cases of the K-shells of nickel, silver, mercury and of the three L-shells of silver and mercury.The agreement with experiment is reasonably good for the K-shell ionization, but only fair in the case of the rather meagre experimental data available for the L-shell. The values obtained for the relative ionization in the K- and L-shells are in good agreement with those to be expected from experiment.

Calculation of the cross section for charge transfer in C 70 + + C60 collisions

2007 ◽  
Vol 105 (4) ◽  
pp. 706-709 ◽  
Author(s):  
G. S. Iroshnikov
Keyword(s):  
Charge Transfer ◽  
Cross Section ◽  
The Cross

Energy dependence of the cross section of the nuclear reaction O16(γ, n)O15

1961 ◽  
Vol 23 ◽  
pp. 513-517 ◽  
Author(s):  
L. Keszthelyi ◽  
I. Berkes ◽  
I. Demeter ◽  
I. Fodor
Keyword(s):  
Nuclear Reaction ◽  
Energy Dependence ◽  
Cross Section ◽  
The Cross
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