XSTAR Home Page Two component XSTAR model fit to the 800 ks Chandra HETG observation of NGC 3783. Model fit performed in xspec11 using the warmabs analytic model. Atomic Data News Atomic data news Iron K shell photoionization cross sections. ADAS Dielectronic Recombination (Badnell). Iron M shell UTA data (Gu). Verner and Yakovlev Photoionization.