Dielectronic recombination (DR) is an important atomic physics process that is relevant to astrophysicalplasma modeling. DR is responsible for the charge state balance as well as the cooling of plasmas, and it is the dominantelectron-ion recombination process for most ions in both photoionized and collisionally-ionized plasmas. Accurate andreliable calculations for DR rate coefficients are needed to analyze the spectra obtained from astrophysical observations.Over the past few years, our group has computed reliable DR and radiative recombination (RR) data for all isoelectronicsequences up through Mg-like ions using a state-of-the-art multi-configuration Breit-Pauli (MCBP) approach. Recently,we have focused our work on the complex third-row M-shell isoelectronic sequences, especially Al-like. Although thereexist some DR calculations for S3+, those calculations were performed only within a non-relativistic LS-couplingapproximation and for electron-ionized, higher temperatures. Fe13+ DR calculations have been completed and testedagainst the Heidelberg heavy-ion Test Storage Ring facility measurements. Semi-relativistic DR cross section and ratecoefficient calculations for Al-like S3+ using the level-resolved distorted-wave AUTOSTRUCTURE program will bepresented. The effect of ground-state fine structure on the DR rates will be discussed. These calculations include final-state-resolved partial DR and RR rate coefficients from the initial ground and metastable levels spanning a temperaturerange of 10 z2 K - 107 z2 K, where z is the initial ionic charge. Our computed Maxwellian DR rate coefficients are fittedinto a simple formula for efficient dissemination of data and ease of use in plasma modeling codes, and comparisons toexisting data will be shown.
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