Supernova Remnant Candidates in the 30 Doradus Nebula

Abstract

We have searched the 30 Doradus nebula, a giant extragalactic H II region, for the presence of embedded supernova remnants using high-resolution radio, optical, and X-ray images. Radio images obtained at 6 and 3.5 cm with the Australia Telescope Compact Array have an angular resolution of ~2''. We compare our radio images with the optical images from the Cerro Tololo Inter-American Observatory to distinguish thermal and possible nonthermal components in the nebula. We have also mapped, for the first time, the extinction across the region at high angular resolution. We identify two sources as supernova remnant candidates in the nebula. Derived physical parameters for the adiabatic phase imply relatively young remnants (~103 yr) evolving in a very dense environment (102 cm-3). We compare our results with high-resolution data from the Chandra X-Ray Observatory, but with only a short exposure these preliminary X-ray data lack the sensitivity to resolve our supernova remnant candidates from intervening hot gas of the diffuse thermal X-ray component of the nebula.