 Dielectronic recombination

A free Electron is resonantly captured while exciting the ionic core, producing a doubly excited state above the parent-ion threshold. Capture becomes permanent recombination only if the state undergoes radiative stabilization rather than autoionization. For resonance $d$, entrance ion $i$, and Maxwellian electrons, ${\alpha }_d=(g_d/(2g_i))(h^2/(2\pi mkT){)}^{3/2}{e}^{-E_d/kT}{A}_{di}^a{A}_{\mathrm{stab}}^r/(A_{\mathrm{tot}}^a+A_{\mathrm{tot}}^r)$. Detailed balance determines the capture rate; a steady population balance determines the survival factor. The rate coefficient has dimensions volume per time.