Central Elemental Abundance Ratios in the Perseus Cluster: Resonant Scattering or SN Ia Enrichment?

We have determined elemental abundance ratios in the core of the Perseuscluster for several elements. These ratios indicate a central dominance of SNIa ejecta similar to that found for A496, A2199 and A3571 (Dupke & White 2000).Simultaneous analysis of ASCA spectra from SIS1, GIS 2&3 shows that the ratioof Ni to Fe abundances is ~ (3.4 +- 1.1) times Solar within the central 4'.This ratio is consistent with (and more precise than) that observed in otherclusters whose central regions are dominated by SN Ia ejecta. Such a large Niover-abundance is predicted by "Convective Deflagration" explosion models forSN Ia such as "W7" but is inconsistent with delayed detonation models. We notethat with current instrumentation the NiK(alpha) line is confused withFeK(beta) and that the Ni over-abundance we observe has been interpreted byothers as an anomalously large ratio of FeK(beta) to FeK(alpha) caused byresonant scattering in the FeK(alpha) line. We argue that a central enhancementof SN Ia ejecta and hence a high ratio of Ni to Fe is naturally explained byscenarios that include the generation of chemical gradients by suppressed SN Iawinds or ram-pressure stripping of cluster galaxies. It is not necessary tosuppose that the intracluster gas is optically thick to resonant scattering ofthe FeK(alpha) line.Comment: 27 pages, 1 figure, accepted for publication in the Astrophysical Journa