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The γ-ray burst of 980425 and its association with the extraordinary radio emission from a most unusual supernova

Kulkarni, S. R. and Frail, D. A. and Wieringa, M. H. and Ekers, R. D. and Sadler, E. M. and Wark, R. M. and Higdon, J. L. and Phinney, E. S. and Bloom, J. S. (1998) The γ-ray burst of 980425 and its association with the extraordinary radio emission from a most unusual supernova. . (Submitted)

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Supernova SN 1998bw exploded in the same direction and at the same time as the gamma-ray burst GRB 980425. Here we report radio observations of this type Ic supernova, beginning 4 days after the gamma-ray burst. At its peak the radio source is the most luminous ever seen from a supernova, νL_ν = 4 x 10^(38) erg/s at 5 GHz. More remarkably, the traditional synchrotron interpretation of the radio emission requires that the radio source be expanding at an apparent velocity of at least twice the speed of light, indicating that this supernova was accompanied by a shock wave moving at relativistic speed. The energy U_e associated with the radio-emitting relativistic electrons must lie between 10^(49) erg < U_e < 10^(52) erg, and thus represents a significant fraction of the total kinetic energy ~10^(51) erg associated with supernova explosions. The presence of a relativistic shock in SN 1998bw suggests a physical connection with the gamma-ray burst GRB 980425. We argue that this represents a second class of gamma-ray burst, with much lower emitted energy ~10^(48) erg in gamma-rays than the two powerful ~10^(53) erg high-redshift gamma-ray bursts previously identified.

Item Type:Report or Paper (Discussion Paper)
Related URLs:
URLURL TypeDescription Paper
Kulkarni, S. R.0000-0001-5390-8563
Higdon, J. L.0000-0003-1397-0586
Bloom, J. S.0000-0002-7777-216X
Alternate Title:The gamma-ray burst of 980425 and its association with the extraordinary radio emission from a most unusual supernova
Additional Information:We gratefully acknowledge Lorne Avery and Gerald Moriarty-Schieven for their help in making the JCMT observations. DAF thanks M. Rupen for useful discussions. SRK thanks A. Readhead for extensive discussions of brightness temperature. The Australia Telescope is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO. The James Clerk Maxwell Telescope is operated by The Joint Astronomy Centre on behalf of the Particle Physics and Astronomy Research Council of the United Kingdom, the Netherlands Organization for Scientific Research, and the National Research Council of Canada. The VLA is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. The research of SRK and of ESP is supported by the National Science Foundation and NASA.
Funding AgencyGrant Number
Commonwealth of AustraliaUNSPECIFIED
Particle Physics and Astronomy Research Council (PPARC)UNSPECIFIED
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)UNSPECIFIED
National Research Council of CanadaUNSPECIFIED
Record Number:CaltechAUTHORS:20190205-131317132
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:92674
Deposited By: Tony Diaz
Deposited On:05 Feb 2019 21:48
Last Modified:02 Nov 2019 17:36

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