Spatial distribution of metal emissions in supernova remnant 3C 397 viewed with Chandra and XMM

We present X-ray equivalent width imaging of 3C 397 for Mg Heα, Si Heα, S Heα, and Fe Kα complex lines with Chandra and XMM-Newton observations. The images revealed that the heavier the element is, the smaller the extent of the element distribution is. The Mg emission is evidently enhanced in the southeastern blow-out region, well along the radio boundary there, and appears to partially envelope the eastern Fe knot. Two bilateral hat-like Si line-emitting structures are along the northern and southern borders, roughly symmetric with respect to the south-east-northwest elongation axis. An S line-emitting shell is located just inside the northern radio and IR shell, indicating a layer of reversely shocked sulphur in the ejecta. A few enhanced Fe features are basically aligned along the diagonal of the rectangular shape of the SNR, which implicates an early asymmetric SN explosion.