Here is more background on how they connected the dots to form this theory:

The only explanation that fitted the observations of the supernova following GRB 111209A was that it was being powered by a magnetar—a tiny neutron star spinning hundreds of times per second and possessing a magnetic field much stronger than normal neutron stars, which are also known as radio pulsars [6]. Magnetars are thought to be the most strongly magnetised objects in the known Universe. This is the first time that such an unambiguous connection between a supernova and a magnetar has been possible.

Paolo Mazzali, co-author of the study, reflects on the significance of the new findings: “The new results provide good evidence for an unexpected relation between GRBs, very bright supernovae and magnetars. Some of these connections were already suspected on theoretical grounds for some years, but linking everything together is an exciting new development.”

This is fascinating stuff and we hope you enjoy the video below which has a general background of gamma rays and some incredible pics!

And check back for updates as this relates to the FRB they found just last year!

thanks to phys.org for the great info