主要内容:
从1999到2002， 在33个Ibc型超新星中，给出它们的射电光变曲线，企图确认一些包含有超新星成分－－即1年左右的射电余辉会很强。但没有。
精彩摘抄:
除了980425， GRB 030329和970508的射电余辉都很强，比超新星的射电辐射至少强两个量级，说明这些超新星中没有偏轴的伽玛暴成分。
文章信息:
| Title: |
| A Radio Survey of Type Ib and Ic Supernovae: Searching for Engine-driven Supernovae |
| Authors: |
| Berger, E.; Kulkarni, S. R.; Frail, D. A.; Soderberg, A. M. |
| Publication: |
| The Astrophysical Journal, Volume 599, Issue 1, pp. 408-418. (ApJ Homepage) |
| Publication Date: |
| 12/2003 |
| Origin: |
| UCP |
| ApJ Keywords: |
| Gamma Rays: Bursts, Radio Continuum: Stars, Stars: Supernovae: General |
| Abstract Copyright: |
| (c) 2003: The American Astronomical Society |
| DOI: |
| 10.1086/379214 |
| Bibliographic Code: |
| 2003ApJ...599..408B |
Abstract
The association of γ-ray bursts (GRBs) and core-collapse supernovae (SNe) of Type
Ib and Ic was motivated by the detection of SN 1998bw in the error box of GRB 980425 and the now secure identification of SN 2003dh in the cosmological GRB 030329. The bright
radio emission from SN 1998bw indicated that it possessed some of the unique attributes expected of GRBs, namely, a large reservoir of energy in (mildly) relativistic ejecta and variable energy input. The two popular scenarios for the origin of SN 1998bw are a typical cosmological burst observed off-axis or a member of a new distinct class of supernova explosions. In the former, about 0.5% of local Type
Ib/c SNe are expected to be similar to SN 1998bw; for the latter no such constraint exists. Motivated thus, we began a systematic program of
radio observations of most reported Type
Ib/c SNe accessible to the Very Large Array. Of the 33 SNe observed from late 1999 to the end of 2002, at most one is as bright as SN 1998bw. From this we conclude that the incidence of such events is <~3%. Furthermore, analysis of the
radio emission indicates that none of the observed SNe exhibit clear engine signatures. Finally, a comparison of the SN
radio emission to that of GRB afterglows indicates that none of the SNe could have resulted from a typical GRB, independent of the initial jet orientation. Thus, while the nature of SN 1998bw remains an open question, there appears to be a clear dichotomy between the majority of hydrodynamic and engine-driven explosions.
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