A surprising new discovery for superluminous supernovae

We have made a surprising discovery of a double-parked light curve of a super-luminous supernova. The dense daily cadence of the La Silla QUEST survey produced a beautifully sampled lightcurve of LSQ14bdq, which was classified as a superluminous SN by PESSTO on 2014 March 22 at a redshift z=0.345. Matt Nicholl spotted the excess flux in the LSQ images when studying the LSQ data for early lightcurve. Matt’s paper (published in ApJ letters) proposes this “bump” is post-shock cooling after breakout of the SN shock from the stellar surface. However the bump is so bright, that a very large explosion energy of a few times 10^52 erg and an extended progenitor radius of a few hundred solar radii are required. Already two alternative theory explanations have come forward by Tony Piro (arXiv - submitted to ApJL) and Kasen, Metzger and Bildsten (arXiv - submitted to ApJ). How common these are is now the next question.