68th Annual Gaseous Electronics Conference/9th International Conference on Reactive Plasmas/33rd Symposium on Plasma Processing
Volume 60, Number 9
Monday–Friday, October 12–16, 2015;
Honolulu, Hawaii
Session HT1: Atomic and Molecular Scattering Data for Plasma and Related Applications Workshop I
8:00 PM–10:00 PM,
Tuesday, October 13, 2015
Room: 301 B
Chair: Alisher Kadyrov, Curtin University
Abstract ID: BAPS.2015.GEC.HT1.2
Abstract: HT1.00002 : Benchmark calculations for electron collisions with complex atoms: accuracy, convergence and completeness*
8:30 PM–9:00 PM
Preview Abstract
Abstract
Author:
Oleg Zatsarinny
(Drake University)
Over the past decade, we have developed a highly flexible $B$-spline $R$-matrix
(BSR) method [1] that has some advantages compared to the standard
$R$-matrix (close-coupling) approach. The two essential refinements are i) the
capability for using the flexible term-dependent one-electron orbitals, and
ii) the use of $B$-splines as a universal and effectively complete basis to
generate the $R$-matrix basis. These features allow us to achieve a high
accuracy in the target description, as well as a truly consistent treatment
of the scattering system. The BSR code was successfully applied to many
problems of electron collisions from atoms and ions, with special emphasis
was placed on complex, open-shell targets. Often considerable \textit{improvement} was obtained in comparison with previous calculations. Many examples can be found in a
recent Topical Review [2].
More recently, the BSR complex has been extended to i) the fully
relativistic Dirac scheme and ii) intermediate energies using the continuum
pseudo-state approach. These extensions allow for an accurate treatment of
\textit{heavy targets} as well as a fully non-perturbative way to handle electron-impact
\textit{ionization}, including such highly correlated processes as ionization plus simultaneous
excitation.
During the last years we developed parallel versions of our BSR and DBSR
codes. They made it possible to carry out large-scale $R-$matrix with
pseudo-states (RMPS) calculations and thereby provide \textit{converged} (with respect to the number of coupled states) results for electron impact excitation of
individual target states. For many systems our calculations revealed
dramatic reductions of the predicted excitation cross-sections at
intermediate energies, due to the strong influence of coupling to the target
continuum. These results raise questions about the absolute normalization in
several published measurements. Our RMPS calculations represent the
extensive and \textit{complete} sets of electron scattering data ready for applications.
\\[4pt]
[1] Zatsarinny O 2006 \textit{Comput. Phys. Commun. }\textbf{174} 273\\[0pt]
[2] Zatsarinny O and Bartschat K 2013 \textit{J. Phys. B: At. Mol. Opt. Phys. }\textbf{46 } 112001
*Research Supported by the United States National Science Foundation
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2015.GEC.HT1.2