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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. - PowerPoint PPT Presentation
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New Classes of Super-Luminous
Supernovae
Shri Kulkarni & Robert QuimbyCaltech, Pasadena
Stellar Evolution (Old Story)
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ZAMS Mass (Mo) Ending<8 C+O White Dwarf8 to 10 Electron Capture -> Neutron Star (:)10 to 25 (say) Fe core -> Neutron Star>25 Fe core -> Black Hole
Note: 1. Neutrino driven explosions can at
most produce 1 Bethe (1051 erg)2. 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
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4Robert Quimby
SN 2006gy
Smith et al. 2008
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
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SN 2007bi: Pair Instability SN
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)
Gal
-Yam
et
al. 2
009
Palomar Transient Factoryhttp://www.astro.caltech.edu/ptf
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P60 classification
telescope
P200 Spectroscopy
P48survey telescope
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2009: PTF Finds Luminous Supernovae
Robert Quimby
PTF09cwl PTF09cnd PTF09atu
Befo
reAf
ter
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Shell Scenario
ejecta and shell both hydrogen poorouter shell expanding at a few 1000 km/senergy 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
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