New Model Supports Connection Between Gamma Ray Bursts And Supernovae

Long-duration gamma-ray bursts are those that last for a few seconds up to several minutes, unlike the more common gamma-ray bursts that last for under a few seconds. The long-duration bursts are suspected of being sustained by the rotational energy of a spinning compact object left behind from a supernova. Superluminous supernovae seem to be associated with these kinds of long-duration bursts, lending support to the idea that they too are powered by a spinning remnant. CfA astronomer Matt Nicholl and four colleagues have proposed a unifying model for superluminous supernovae and long-duration gamma-ray bursts in which a spinning neutron star has a slight misalignment between its spin axis and its magnetic axis. The consequence is that substantial fractions of the spinning power are supplied both to the supernova and to a jet of particles moving at speeds close to the speed of light that enabled the long burst. Moreever, the scientists are able to predict the radio emission and thermal wind effects, and to address some of the transient effects that appear in these dramatic events. Reference: “The GRB–SLSN Connection: Misaligned Magnetars, Weak Jet Emergence, and Observational Signatures” by Ben Margalit, Brian D Metzger, Todd A Thompson, Matt Nicholl and Tuguldur Sukhbold, 9 January 2018, MNRAS.DOI: 10.1093/mnras/sty013