The X-Ray Light Curve of the Very Luminous Supernova SN 1978K in NGC 1313
Abstract
We present the 0.5-2.0 keV light curve of the X-ray luminous supernova SN 1978K in NGC 1313, based on six ROSAT observations spanning 1990 July to t994 July. SN 1978K is one of a few supernovae or supernova remnants that are very luminous (∼1039-1040 ergs s-1) in the X-ray, optical, and radio bands, and the first, at a supernova age of 10-20 yr, for which sufficient data exist to create an X-ray light curve. The X-ray flux is approximately constant over the 4 yr sampled by our observations, which were obtained 12-16 yr after the initial explosion. Three models exist to explain the large X-ray luminosity: pulsar input, a reverse shock running back into the expanding debris of the supernova, and the outgoing shock crushing of cloudlets in the debris field. Based upon calculations of Chevalier & Fransson, a pulsar cannot provide sufficient energy to produce the soft X-ray luminosity. Based upon the models and the light curve to date, it is not possible to discern the evolutionary phase of the supernova.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 1996
- DOI:
- 10.1086/176639
- Bibcode:
- 1996ApJ...456..187S
- Keywords:
-
- GALAXIES: INDIVIDUAL NGC NUMBER: NGC 1313;
- STARS: PULSARS: GENERAL;
- STARS: SUPERNOVAE: INDIVIDUAL ALPHANUMERIC: SN 1978K;
- ISM: SUPERNOVA REMNANTS;
- X-RAYS: STARS