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[82.03] Atomic Data and Spectral Processes in XSTAR v.2

M. Bautista, T. Kallman (NASA/ GSFC)

One important improvement of XSTAR v.2 over its first version is the extension of the atomic database and new or improved treatment of spectral processes. The database is particularly focused towards X-rays and includes collisional and radiative transitions, photoionization, collisional ionization, radiative and dielectronic recombination, three-body recombination, and auger rates for ground and excited levels of every ion model. The database collects the best data from many sources includeing CHIANTI, HULLAC, TOPbase, ADAS, NIST, and the Iron Project. Two particular features of the database are the incorporation of photoionization cross sections from the Opacity Project for all levels of every ion, and state specific recombination rates. For the H and He isoelectronic series, the recombination cascade problem was solved for every ion and collisional-recombination models were constructed and implemented into XSTAR v.2. These models are designed to work for densities of up to 10¹⁸ cm^-3 and temperatures between 100 and 10⁹ K. Another important feature is that every ion model is designed to converge to LTE under appropriate conditions. Detailed description of the database and models is presented. Some apllications of the model are also shown.