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How Common are Engines in Ib/c Supernovae?

Edo Berger
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Abstract

The association of gamma-ray bursts (GRBs) and core-collapse supernovae (SNe) of Type Ib and Ic was motivated by the detection of SN1998bw in the error box of GRB980425 and the now-secure identification of a SN1998bw-like event in the cosmological GRB030329. The bright radio emission from SN1998bw 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. Here we discuss the results of a systematic program of radio observations of most reported Type Ib/c SNe accessible to the Very Large Array, designed to determine the fraction of Type Ib/c SNe driven by an engine. We conclude that: (i) the incidence of such events is low, <3%, and (ii) there appears to be a clear dichotomy between the majority of hydrodynamic explosions (SNe) and engine-driven explosions (GRBs)

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Edo Berger. 2003-09-25. How Common are Engines in Ib/c Supernovae?. https://doi.org/10.1007/3-540-26633-x_58

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