Dielectronic recombination occurs where an electron recombines with the ion in an excited state and excites a second electron while doing so. The ion is left in a highly excited state, which may then autoionize (thereby inverting the dielectronic recombination and converting the process into a simple scattering event) or it may radiatively decay when one of the excited electrons radiatively decays, creating a satellite line. A satellite line is so named because it will be at a slightly longer wavelength than the normal transition from an electron in that energy level. The due to the recombined electron which is also in an excited level.
For a complete description of how dielectronic recombination and satellite lines are treated in APEC and ATOMDB, please read the memo.