ChandraObservation of the Magellanic Cloud Supernova Remnant 0454−67.2 in N9

A Chandra observation has defined the extent of the SNR B 0454-692 in the LMCH II region N9. The remnant has dimension 2.3" x 3.6" and is elongated in theNS direction. The brightest emission comes from a NS central ridge whichincludes three bright patches. There is good agreement between X-ray and [OIII] and [S II] morphology. The remnant is old enough so that optical data givemore information about dynamics than do the X-ray data. The SN energy releasewas >= 4 x 10^50 ergs and the age is ~3 x 10^4 years. There are severalunresolved sources nearby but none are clearly associated with the remnant. TheX-ray spectrum is soft and indicates enhanced Fe abundance in the centralregion, consistent with a Type Ia SN origin, but a Type II origin cannot beruled out.Comment: AASTeX, 20 pages including 5 figures. Accepted for publication in The Astrophysical Journal. Figures have been reduced in resolution for space requirements; full-resolution figures may be requested by email to rosanina@astro.uiuc.ed