Type "IIn" Supernovae: A Search for Radio Emission
Abstract
We have conducted a search using the Very Large Array for radio emission from members of Schlegel's (1990) proposed supernova subclass, Type IIn, which show optical characteristics indicative of shock interaction with dense circumstellar matter. None has been detected to upper limits of <~ 0.2 mJy. We compare the corresponding radio luminosity upper limits for these supernovae to the radio luminosities for known Type M radio supernovae. Although broadly similar optically to the unusual Type IIn SNs 1988Z and 1986J, none of the observed supernovae could be nearly as radio luminous. We find that the radio behavior of most Type IIn supernovae may not be significantly different from that of other more normal Type II supernovae. It therefore appears that optical spectra alone are not sufficient to predict radio luminosity and that intrinsically radio luminous supernovae, such as SNs 1988Z and 1986J, are quite rare.
- Publication:
-
The Astronomical Journal
- Pub Date:
- March 1996
- DOI:
- 10.1086/117872
- Bibcode:
- 1996AJ....111.1271V
- Keywords:
-
- RADIO LINES: STARS;
- SUPERNOVAE: GENERAL