Electric-field-induced mixing of high Rydberg-state levels in dielectronic recombination:Mg1+andCa1+target ions

Abstract

The effect on the dielectronic recombination cross section of electric-field-induced mixing of high Rydberg-state (HRS) levels is determined, for both ${\mathrm{Mg}}^{1+}$ and ${\mathrm{Ca}}^{1+}$ target ions. After diagonalizing the energy matrix, ${\sigma }_n^{\mathrm{DR}}$ is calculated in the isolated resonance approximation as a function of n, the principal quantum number of the HRS electron. From this result, both the total cross section, ${\sigma }^{\mathrm{DR}\mathrm{\equiv }{\mathcal{J}}_{n_{\mathrm{}}{\sigma }_n^{\mathrm{DR}}}}$, and the total cross section integrated over energy, ${\Omega }^{\mathrm{DR}}$≡F ${\mathrm{de}}_c$ ${\sigma }^{\mathrm{DR}}$, are obtained. The agreement between theory and experiment for ${\Omega }^{\mathrm{DR}}$ is very good in the case of ${\mathrm{Mg}}^{1+}$, while roughly a factor of 2 discrepancy still exists for ${\mathrm{Ca}}^{1+}$.