A search for relativistic ejecta in a sample of ZTF broad-lined Type Ic supernovae

Understand

The dividing line between gamma-ray bursts (GRBs) and ordinary stripped-envelope core-collapse supernovae (SNe) is yet to be fully understood.

• Observationally mapping the variety of ejecta outcomes (ultra-relativistic, mildly-relativistic or non-relativistic) in SNe of Type Ic with broad lines (Ic-BL) can provide a key test to stellar explosion models.
• However, this requires large samples of the rare Ic-BL events with follow-up observations in the radio, where fast ejecta can be probed largely free of geometry and viewing angle effects.
• Here, we present the results of a radio (and X-ray) follow-up campaign of 16 SNe Ic-BL detected by the Zwicky Transient Facility (ZTF).