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4 Conclusion

The purpose of the present calculations has been to generate cross sections for the electron impact excitation of Si I in the Born approximation. These atomic cross sections are potentially useful as required data for modelers of astrophysical plasmas, and should also serve as a guide for more advanced calculations on the complex open-shell system represented by Si I.

Results are given over a large energy range, but due to the limitations of the Born approximation, only those results above 60 eV may be considered to have good accuracy. Used with this caution, the present results may be helpful to users of atomic data.


 
Table 2: Oscillator strengths for Si I for the transitions 3p2(3P$_0)\rightarrow $3pns(3P1) and 3p2(3P$_0)\rightarrow $3pnd(3P1,3D1)

\begin{tabular}
{cccc} 
\hline
 & This & & Other \\  3p to & Calculation & Exper...
 ... 0.0184 & & $0.0072^g, 0.0381^n$\space \\ \\ [0.02cm] \hline
\hline\end{tabular}

  • [a]Hofmann(1969): uses vacuum-UV intensity calibration method.
  • [b]Saloman(1990): sputter-initiated resonance ionization spectroscopy.
  • [c]Savage & Lawrence (1966): uses phase-shift method.
  • [d]Smith et al. (1987): uses Hook and emission methods.
  • [e]Garz (1973): measurements in emission in a wall-stabilized arc.
  • [f]O'Brian & Lawler (1991): time-resolved laser-induced fluoresence on a Si beam.
  • [g]Morton (1991): compilation of atomic data.
  • [h]Hibbert (1979): uses configuration interaction expansions.
  • [i]Mendoza & Zeippen (1988): close-coupling approximation.
  • [j]Iglesias et al. (1992): uses parametric Yukawa potentials.
  • [k]Mukherjee & Ohno (1989): time-dependent coupled Hartree-Fock theory.
  • [l]Nahar (1993): close-coupling approximation.
  • [m]Nahar & Pradhan (1993): close-coupling approximation.
  • [n]Verner et al. (1994): compilation of oscillator strengths.


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