Speaker
Description
Since the launch of Swift, it has detected more than 1500 GRBs, ~90% of which are long duration GRBs. Almost every spectroscopically confirmed SN associated with a long GRB has been hydrogen and helium poor with broad lines (Ic-BL), indicating a stripped massive star progenitor with fast winds that produced a highly-collimated jet viewed on-axis. A critical prediction of this progenitor model is that there should be a large number of off-axis jets accompanied by Ic-BL SNe - but this has yet to be observationally confirmed. Years after the explosion, the off-axis jet will have decelerated and become spherical, resulting in a late-rising radio light curve. Here, I will present late time radio observations of a sample of Ic-BL SNe that have been shown to have exploded in the same host environments as long GRBs, making them some of the strongest candidates for off-axis GRBs to-date. I will use these observations to place constraints on the existence of off-axis jets within this sample and within the local universe, which will help us better understand the nature of the long GRBs detected by Swift.
