Photorecombination of Electrons in Dense Plasmas

2000 ◽  
Vol 55 (3-4) ◽  
pp. 457-459
Author(s):  
Young-Dae Jung ◽  
Soo-Yong Rhee
Keyword(s):  
Cross Section ◽  
Nuclear Charge ◽  
Detailed Balance ◽  
Debye Length ◽  
Photoionization Cross Section ◽  
Bohr Radius ◽  
Free Electrons ◽  
Dense Plasmas ◽  
Continuum States ◽  
Plasma Screening

Abstract The plasma screening effect on the photorecombination of free electrons, with ions in a weakly plas-ma is investigated. The recombination cross section is obtained by the principle of detailed balance with the photoionization cross section of the hydrogenic ion including the plasma screening effects on the bound and continuum states of the electron. It is found that the plasma screening effects on the recom-bination cross section are less than 11% when the Debye length (Λ) is greater than ten times of the Bohr radius (az) of the hydrogenic ion with nuclear charge Z

A GTO basis set calculation of properties of the continuum. Photoionization and resonances of He

1992 ◽  
Vol 70 (2) ◽  
pp. 513-519 ◽  
Author(s):  
Roberto Moccia ◽  
Pietro Spizzo
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Photoionization Cross Section ◽  
Basis Set ◽  
Basis Sets ◽  
Gaussian Basis Sets ◽  
Continuum States ◽  
K Matrix ◽  
The Continuum ◽  
Autoionizing States

By using the K-matrix technique for the continuum states that was previously employed with particularly diffuse L2 basis sets, it is shown that GTO bases are also capable of yielding accurate values for the properties belonging to the electronic continuum. The method has been tested for helium and proved of satisfactory accuracy also for the analysis of the autoionizing states. The results include the phase shifts of the continuum states of the 1Seand 1P° manifolds, the properties of the lowest resonances of these symmetries, the ground state photoionization cross section, and the S contribution to the 1s2p1P° photoionization cross section. The results obtained suggest that the proposed technique should be useful for computing molecular differential photoionization cross sections by exploiting the widely used codes that employ GTO bases. Keywords: photoionization, Gaussian basis sets, helium, autoionizing states.

Elastic electron–ion collisions in a Lorentzian plasma

2000 ◽  
Vol 63 (1) ◽  
pp. 79-88 ◽  
Author(s):  
YOUNG-DAE JUNG ◽  
WOOPYO HONG
Keyword(s):  
Spectral Index ◽  
Cross Section ◽  
Debye Length ◽  
Eikonal Approximation ◽  
Elastic Electron ◽  
Screening Effect ◽  
Ion Collisions ◽  
Plasma Screening ◽  
Line Trajectory ◽  
Ion Collision

Plasma screening effects on elastic electron–ion collision processes in a Lorentzian (kappa)-distribution plasma are investigated using the eikonal method. The electron–ion interaction potential is obtained by introducing a plasma dielectric function εκ. The semiclassical straight-line trajectory method is applied to the path of a projectile electron in order to investigate the variation of the eikonal phase as a function of impact parameter and spectral index κ. In the first-order eikonal approximation, the dynamic plasma screening effect on the eikonal phase is found to be a static screening effect, and depends only on the Debye length and spectral index. The position of the maximum of the differential elastic eikonal cross-section recedes from the ion core with increasing spectral index. The plasma screening effect on the eikonal cross-section increases with decreasing spectral index.

Electronic and Optical Properties of Deep Donors in Hydrogenated AlxGa1-xAs:Si.

1989 ◽  
Vol 163 ◽  
Author(s):  
R. Mostefaoui ◽  
R. Legros ◽  
J. Chevallier ◽  
C.W. Tu ◽  
R.F. Kopf
Keyword(s):  
Optical Properties ◽  
Barrier Height ◽  
Cross Section ◽  
Energy Barrier ◽  
Reference Sample ◽  
Photoionization Cross Section ◽  
Energy Curve ◽  
Free Electrons ◽  
Section Versus ◽  
Kinetics Of

Abstract:Transient conductivity and photoconductivity experiments have been performed on hydrogenated Al0.37Ga0.63As:Si epilayers. The recapture kinetics of free electrons on the remaining deep donors is significantly affected under hydrogena-tion. The energy barrier height for capture on the deep donors drops from 210mev in the reference sample to 40mev in the hydrogenated sample. We also note a shift toward higher energies of the photoionization cross section versus photon energy curve. Different models are proposed for explaining the data.

Dielectronic Recombination in the Average-Atom Model

1988 ◽  
Vol 102 ◽  
pp. 215
Author(s):  
R.M. More ◽  
G.B. Zimmerman ◽  
Z. Zinamon
Keyword(s):  
Detailed Balance ◽  
Systematic Errors ◽  
Dielectronic Recombination ◽  
Rate Equations ◽  
Strong Correlations ◽  
Dense Plasmas ◽  
Atom Model ◽  
New Feature ◽  
Average Atom Model ◽  
Attachment Process

Autoionization and dielectronic attachment are usually omitted from rate equations for the non–LTE average–atom model, causing systematic errors in predicted ionization states and electronic populations for atoms in hot dense plasmas produced by laser irradiation of solid targets. We formulate a method by which dielectronic recombination can be included in average–atom calculations without conflict with the principle of detailed balance. The essential new feature in this extended average atom model is a treatment of strong correlations of electron populations induced by the dielectronic attachment process.

XUV Absorption Spectra of Carbon Ions

1988 ◽  
Vol 102 ◽  
pp. 71-73
Author(s):  
E. Jannitti ◽  
P. Nicolosi ◽  
G. Tondello
Keyword(s):  
Absorption Spectra ◽  
Cross Section ◽  
Theoretical Calculations ◽  
Photoionization Cross Section ◽  
Carbon Ions

AbstractThe photoabsorption spectra of the carbon ions have been obtained by using two laser-produced plasmas. The photoionization cross-section of the CV has been absolutely measured and the value at threshold, σ=(4.7±0.5) × 10−19cm2, as well as its behaviour at higher energies agrees quite well with the theoretical calculations.

scholarly journals Photoionization Cross-Sections of Carbon-Like N+ Near the K-Edge (390–440 eV)

Atoms ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 27
Author(s):  
Jean-Paul Mosnier ◽  
Eugene T. Kennedy ◽  
Jean-Marc Bizau ◽  
Denis Cubaynes ◽  
Ségolène Guilbaud ◽  
...  
Keyword(s):  
High Resolution ◽  
Cross Section ◽  
Cross Sections ◽  
Experimental Studies ◽  
Photoionization Cross Section ◽  
Theoretical Work ◽  
Rydberg Series ◽  
R Matrix ◽  
Resonance Strengths ◽  
Nitrogen Ion

High-resolution K-shell photoionization cross-sections for the C-like atomic nitrogen ion (N+) are reported in the 398 eV (31.15 Å) to 450 eV (27.55 Å) energy (wavelength) range. The results were obtained from absolute ion-yield measurements using the SOLEIL synchrotron radiation facility for spectral bandpasses of 65 meV or 250 meV. In the photon energy region 398–403 eV, 1s⟶2p autoionizing resonance states dominated the cross section spectrum. Analyses of the experimental profiles yielded resonance strengths and Auger widths. In the 415–440 eV photon region 1s⟶(1s2s22p2 4P)np and 1s⟶(1s2s22p2 2P)np resonances forming well-developed Rydberg series up n=7 and n=8 , respectively, were identified in both the single and double ionization spectra. Theoretical photoionization cross-section calculations, performed using the R-matrix plus pseudo-states (RMPS) method and the multiconfiguration Dirac-Fock (MCDF) approach were bench marked against these high-resolution experimental results. Comparison of the state-of-the-art theoretical work with the experimental studies allowed the identification of new resonance features. Resonance strengths, energies and Auger widths (where available) are compared quantitatively with the theoretical values. Contributions from excited metastable states of the N+ ions were carefully considered throughout.

Measurement of the photoionization cross section of the Li atom at the 2Plevel

1977 ◽  
Vol 7 (10) ◽  
pp. 1305-1306 ◽  
Author(s):  
Nikolai V Karlov ◽  
B B Krynetskiĭ ◽  
O M Stelmakh
Keyword(s):  
Cross Section ◽  
Photoionization Cross Section
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