A Relativistic Type Ibc Supernova Without a Detected Gamma-ray Burst

Understand

Long duration gamma-ray bursts (GRBs) mark the explosive death of some massive stars and are a rare sub-class of Type Ibc supernovae (SNe Ibc).

• They are distinguished by the production of an energetic and collimated relativistic outflow powered by a central engine (an accreting black hole or neutron star).
• Observationally, this outflow is manifested in the pulse of gamma-rays and a long-lived radio afterglow.
• To date, central engine-driven SNe have been discovered exclusively through their gamma-ray emission, yet it is expected that a larger population goes undetected due to limited satellite sensitivity or beaming of the collimated emission away from our line-of-sight.