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New Classes of Super-Luminous Supernovae. Shri Kulkarni & Robert Quimby Caltech, Pasadena. Stellar Evolution (Old Story). Note: Neutrino driven explosions can at most produce 1 Bethe (10 51 erg) If so, supernovae with >1Bethe must have a central engine or a pure thermonuclear event.
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New Classes of Super-Luminous Supernovae • Shri Kulkarni & Robert Quimby • Caltech, Pasadena
Stellar Evolution (Old Story) • Note: • Neutrino driven explosions can at most produce 1 Bethe (1051 erg) • If so, supernovae with >1Bethe must have a central engine or a pure thermonuclear event
Exotic Endings • The central object is an active source of energy • Magnetar (highly magnetized neutron star) • Collapsar (rotating black hole – Gamma Ray Bursts) • Pair Instability supernovae • Expected ending for massive stars (100 Msun) • The most massive thermonuclear explosions in the Universe • Do not expect such events at low redshift
SN 2006gy • Peak absolute magnitude nearly -22 • Brighter than -21 mag for ~100 days • Integrated light >1051 erg • See: Ofek+ 2007, Smith+ 2007, Smith & McCray 2007, Agnoletto+ 2009, Kawabata+ 2009... 50 kpc ~600 pc Smith et al. 2008 Robert Quimby
Optical light curve decay rate consistent with the production of ~7 M of 56Ni • Iron abundance in nebular spectra also consistent with the decay of ~4-7 M of 56Ni (Gal-Yam 2009) SN 2007bi: Pair Instability SN Gal-Yam et al. 2009
Palomar Transient Factoryhttp://www.astro.caltech.edu/ptf P60 classification telescope P48 survey telescope P200 Spectroscopy
2009: PTF Finds Luminous Supernovae PTF09atu PTF09cwl PTF09cnd Before After Robert Quimby
Shell Scenario • ejecta and shell both hydrogen poor • outer shell expanding at a few 1000 km/s • energy injected from with in
Conclusions • A new class of supernovae ten times brigther and ten times more energy release than ordinary supernovae • The origin of these supernovae is unclear but likely entirely are the largest thermonuclear explosions in the Universe • The findings were unexpected • Easy to detect such supernovae with JWST even at high redshift (z=10). • May have bearing on how the youngest stars in the Universe die