Si XII X-ray Satellite Lines in Solar Flare Spectra

The temperature dependence of the Si XII n=3 and n=4 dielectronic satellite line features at 5.82A and 5.56A respectively, near the Si XIII 1s(sup 2)-1s3p and 1s(sup 2)-1s4p lines (5.681A and 5.405A), is calculated using atomic data presented here. The resulting theoretical spectra are compared with solar flare spectra observed by the RESIK spectrometer on the CORONAS-F spacecraft. The satellites, like the more familiar n=2 satellites near the Si XIII 1s(sup 2)-1s2p lines, are formed mostly by dielectronic recombination, but unlike the n=2 satellites are unblended. The implications for similar satellite lines in flare Fe spectra are discussed.