COMPARATIVE MORPHOLOGICAL ANALYSIS OF PUPPIS A AT RADIO, INFRARED, OPTICAL, AND X-RAY WAVELENGTHS

We present a new radio image of the supernova remnant Puppis A obtained with the Molonglo Observatory synthesis telescope (MOST) and the Parkes telescope, and infrared images of Puppis A and its surrounding medium obtained with the IRAS. We compare the remnant morphologies at radio, infrared, optical, and X-ray wavelengths. The radio image, which includes large-scale emission, shows a clumpy shell of emission with moderate central brightness. The infrared observations have the advantage of offering a detailed look at the medium into which the remnant is expanding. From the IR data, we find evidence of the remnant's expansion into a strong density gradient (distinct from the more gentle gradient of the Galactic plane), which had been inferred from previous X-ray observations. A strong, previously believed, isolated knot of enhanced X-ray and radio emission is a region of enhanced infrared emission as well, and it is part of a larger molecular complex with which the remnant is interacting. Detailed correlative analysis of the infrared, radio, and X-ray emission shows that the IR emission correlates very well with the X-ray emission, confirming the idea that the IR emission arises from dust that is collisionally heated by the shocked gas.