Constraints on Type Ia Supernova Models from X‐Ray Spectra of Galaxy Clusters

We present constraints on theoretical models of Type Ia supernovae usingspatially resolved ASCA X-ray spectroscopy of three galaxy clusters: Abell 496,Abell 2199 and Abell 3571. All three clusters have central iron abundanceenhancements; an ensemble of abundance ratios are used to show that most of theiron in the central regions of the clusters comes from SN Ia. Theseobservations are consistent with the suppressed galactic wind scenario proposedby Dupke and White (1999). At the center of each cluster, simultaneous analysisof spectra from all ASCA instruments shows that the nickel to iron abundanceratio (normalized by the solar ratio) is Ni/Fe ~ 4. We use the nickel to ironratio as a discriminator between SN Ia explosion models: the Ni/Fe ratio ofejecta from the "Convective Deflagration" model W7 is consistent with theobservations, while those of "delayed detonation" models are not consistent atthe 90% confidence level.Comment: 20 pages, 2 figures, accepted by The Astrophysical Journa