What if you take the biggest, most massive stars, and watch them explode? Do they look any different from a normal supernova? Let’s find out with today’s supernova iPTF14hls!
All stars die, but not all stars die the same. Some will explode and leave no trace behind. These special explosions with no trace are called pair-instability supernovae (PISNe) and only happen in the most massive of stars. Today’s paper from 2009 investigates a unique supernova, SN 2007bi, that was initially thought to be the first PISN ever observed.
How do the most massive stars explode? A new model of massive stars predicts new observational evidence.
When the supernova impostor SN2009ip brightened to a V-band absolute magnitude of -17.7 near the end of 2012, the outburst was classified as a Type IIn supernova and many observers thought the star had finally exploded for good. In this paper, however, the authors present several months of multiband imaging of transient 2012b and argue that the low limit on the nickel mass and lack of most heavy elements in the ejecta suggest the progenitor is still around, and that transient 2012b was produced instead by the collision of two massive shells, possibly ejected by the pulsational pair instability.