abstract for workshop

[Libo Zhao <zhao@hal.physast.uga.edu>]

I am submitting my abstract (LaTex form) for NASA Laboratory Astrophysics
Workshop. I have submitted my registration form.

Thanks
Libo Zhao


\documentclass[preprint,aps,pra,showpacs]{revtex4}
%-------------------------------------------------------------------
\begin{document}
\title{Charge transfer between S$^{2+}$ and He: A comparative study of
quantal and semiclassical approaches}
\author{L. B. Zhao}
\author{P. C. Stancil}
\affiliation{Department of Physics and Astronomy and the Center for
         Simulational Physics\\
         University of Georgia, Athens, GA, 30602-2451}

\author{J.-P. Gu, G. Hirsch\footnote{deceased}, and R. J. Buenker}
\affiliation{Fachbereich C-Mathematik und Naturwissenschaften,
       Bergische Universit\"at
       Wuppertal, D-42097 Wuppertal, Germany}
%-----------------------
\author{T. W. Imai and M. Kimura}
\affiliation{Graduate School of Sciences, Kyushu University, Fukuoka
812-8581,
       Japan}
%-----------------------
%\draft
\date{\today}
\begin{abstract}
A comparative study on charge transfer in collisions of ground-state
S$^{2+}$
ions with He has been performed within fully quantal and semiclassical
molecular-orbit close-coupling approaches. The processes for capture into
S$^+$($^4$S$^o$, $^2$D$^o$, $^2$P$^o$) + He$^+$ are taken into account.
Quantal and semiclassical cross sections were evaluated, respectively, in
the
diabatic and adiabatic representations and found to be in good agreement.
The calculations show that at collision energies below about 40 eV/u, the
charge-transfer processes are dominated by S$^{2+}$($^3$P) + He $\to$
S$^+$($^2$D$^o$) + He$^+$, and capture into the $^2$P$^o$ and $^4$S$^o$
states
become comparable with that into the $^2$D$^o$ state above 40 eV/u and 600
eV/u,
respectively. The multireference single- and double-excitation
configuration-interaction method was utilized to obtain adiabatic
potentials and nonadiabatic coupling matrix elements. A detailed
comparison of
quantal and semiclassical transition probabilities is discussed.
State-selective
and total rate coefficients are presented with temperatures between 10,
000 K
and 5.0 $\times$ 10$^6$ K.
\end{abstract}
\pacs{34.10.+x, 34.20.Mq, 34.70.+e}
\maketitle
\end{document}