Dielectronic recombination rates for ions of the sodium sequence

The dielectronic recombination (DR) rate coefficient ${\alpha }^{\mathrm{DR}}$ is explicitly calculated for Mo, Fe, and Ar target ions of the Na isoelectronic sequence (11 electrons). This work is an extension of a previous study of DR for ${\mathrm{Mo}}^{31+}$ ions. Both $\Delta n\ne 0$ and $\Delta n=0\mathrm{}$ transitions are considered in detail, with full $\mathrm{LS}$ coupling. The radiative and Auger cascade effects are found to be important, especially for high Rydberg states, and are included in the final rate-coefficient estimate. Scaling of ${\alpha }^{\mathrm{DR}}$ with ionic charge and free-electron temperature is discussed.