diversity of supernova-hypernova propertiesinoue/grb2010web/...the final fates of single stars • m...
TRANSCRIPT
![Page 1: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/1.jpg)
Supernova-Hypernova
K. Nomoto (IPMU, U. Tokyo)
Diversity of
Properties
![Page 2: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/2.jpg)
Diversity & Peculiarities of Supernovae • Ultra-Luminous SNe (IIn, II-L, Ic)
Pair Instability ?Core-Collapse ? GRB ?CSM Interaction ?
• Ultra-Faint SNe (IIn, Ic): SN Impostor ? (peculiar) SN Ia ? Super AGB ? Fallback SN ? non-SN GRB ?
• GRB-SN : • Magnetar ?
![Page 3: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/3.jpg)
The Final Fates of Single Stars• M < 0.08 M Brown Dwarf• 0.08 -- 0.46 M He White Dwarf• 0.46 -- 8 M C+O White Dwarf• 8 M -- Mup O+Ne+Mg WD• Mup -- 10 M ONeMg–cc-SN + NS• 10 M -- Mns Fe-cc-Supernova + NS• Mns -- 140 M Fe-cc-Supernova + BH• 140 -- 300 M Pair Instability SN• 300 -- 105 M SN + BH• 105 M < M BH(H)
![Page 4: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/4.jpg)
(I) 8 – 10 M StarsSuper AGB Stars (1.07 M < Mcore < MCh)
degenerate ONeMg core • 8 M < M < Mup
ONeMg White DwarfsMup ~ 9 M ( Z )
• Mup < M < 10 M (Mcore ~ MCh)ONeMg Core Collapse SNe II due to Electron Capture
Nomoto 1984
![Page 5: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/5.jpg)
Electron Capture in 8-10 M Stars
• 24Mg(e-,ν)24Na(e-,ν)24Ne
� ρ>4.0×109gcm-3
• →collapse
Accretion-Induced Collapse of a WD ?
![Page 6: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/6.jpg)
Presupernova Density StructureNomoto-Umeda et al.-
Density
Steep Density Gradient
![Page 7: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/7.jpg)
9M StarNeutrino Heating Weak Explosion
Steep Density GradientEexp =11050 erg
Mej=0.014M
Nucleosynthesis
Kitaura, Janka, & Hillebrandt (2006)
M(56Ni)=0.002-0.003M
![Page 8: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/8.jpg)
56Co-decay
![Page 9: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/9.jpg)
Faint SNe IIn: SN 2008S, NGC300-OT(Della Valle et al. 08;Pastorelle 08;Botticella et al. 09)
Progenitor =Super AGB star ?
(Prieto et al. 08,09Thompson et al. 08)
SN Impostor ?(Smith et al. 09Bond et al. 09Berger et al. 09)
Botticellar et al. 2009
-14
![Page 10: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/10.jpg)
(II) M > 10 M : Fe Core Collapse
(20 M; z=0.02)
Ohkubo et al.
![Page 11: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/11.jpg)
SNe II-P (Smartt 08)
M(56Ni) Radioactive tail
Plateau
![Page 12: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/12.jpg)
(Smartt 2008)
M (56Ni) – Main Sequence Mass
![Page 13: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/13.jpg)
Faint Supernovae
SN 2008ha (I ?)
2005cz (Ib)(Kawabata+)
2005E (Ib) (Peretz+)
2008S (IIn)(Kawabata et al. 2010 Nature in press)
![Page 14: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/14.jpg)
Faint SN 2008ha: Spectra(narrow)
Foley et al. (2009) Filippenko (1997)
SN Ia
SN I 2008ha
![Page 15: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/15.jpg)
Fallback model for SN 2008ha- CO star core-collapse model
Moriya et al.
(13 M 2.7 M)
![Page 16: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/16.jpg)
Fallback in Jet-induced ExplosionJet
BH/NS BH
Edep: Energy deposition rate
(Rotation, B etc.)
.
cf. “Collapsar”(e.g., MacFadyen et al. 01)
Magnetorotational Supernovae(e.g., Moiseenko et al. 06)
Jet
(Tominaga et al. 2007)
Same mass and explosion energy40M 1.5x1052erg
Maeda et al.Mazzali et al.Modjaz et al.
[OI] 6300A (SUBARU
![Page 17: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/17.jpg)
Della Valle et al. 2006
non-SN GRBGRB 060614
Fynbo et al. 2006Gal-Yam et al. 2006
Dark Hypernova
![Page 18: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/18.jpg)
GRB 030329 / SN 2003dh
Hjorth et al (2003)Stanek et al (2003) ;
![Page 19: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/19.jpg)
Ia
Ic
Ib
94I
97ef
98bw
HeCaO
SiII
Hyper-novae
Spectra of Supernovae & Hypernovae
Hypernovae:
broad features
blended lines
“Large mass at high velocities”
Ic: no H,
no strong He,
no strong Si
Patat et al. (1999)
![Page 20: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/20.jpg)
SN1994I
SN2006aj
SN2003lw
SN1997efSN2002ap
SN2003dh
SN1998bw
GRB-SN
![Page 21: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/21.jpg)
GRB-Supernovae
GRB SN MCO/M Mms/M E/1051erg M(56Ni)/M
980425 1998bw 14 40 30 0.4
030329 2003dh 11 35 40 0.35
031203 2003lw 16 45 60 0.55
Three GRB-SNe = all Type Ic Hypernovae
E > 1052 erg (~10×normal SN)Large Mms →Black Hole Forming SNe
Aspherical
![Page 22: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/22.jpg)
![Page 23: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/23.jpg)
M(56Ni) - M(main Seq)
23
![Page 24: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/24.jpg)
Hypernova in Prague
![Page 25: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/25.jpg)
Hypernova in Prague
![Page 26: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/26.jpg)
Non-GRB, peculiar SN Ib 2005bf
MAGNUM (U. Tokyo)SN2005bf
![Page 27: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/27.jpg)
SN Ib 2005bfAnupama et al. (2005)Tominaga et al. (2005)Folatelli et al. (2006)
Double PeaksM(56Ni) =0.07 M : 1st
=0.3 M : 2nd
![Page 28: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/28.jpg)
SN 2005bf: Light Curve @ Late Phases
Maeda et al. (astro-ph/0705.2713)(ApJ 2007 Sep)
SUBARU obs
M(56Ni) < 0.07 M
![Page 29: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/29.jpg)
1st peak: 56Ni decay 2nd peak: Magnetized Pulsar ?
L=L0(t/t0)β
L0=8x1043erg/s(*)
T0=60day
β = -4 (n = 2)
(*) If dipole, e.g.,
B0~1015 G, P0~10 ms
Maeda et al. (astro-ph/0705.2713)(ApJ 2007 Sep)
![Page 30: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/30.jpg)
SN 2005bf: Unipolar Explosion ? (NS kick ?)
Maeda, et al. ApJ 2007
![Page 31: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/31.jpg)
Spectropolarimetry with Subaru
31Tanaka et al. 2009
SubaruVLT
![Page 32: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/32.jpg)
SN 2005bf
32Tanaka et al. 2009
PolarizationLarge asymmetry
Nebular spectraUnipolar?
2nd PeakMagnetic power?
![Page 33: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/33.jpg)
Brightest Hypernova: 1999as @z=0.127
E ~ 3×1052erg Mms ~ 60M
MCO ~ 20M
M(56Ni) ~ 5.4M
SN 1999as
mag
(Deng et al. )
(Knop et al.)
![Page 34: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/34.jpg)
Extremely Luminous SNeSN Ic 2007bi (Pair-Instability?)
M(56Ni) ~ 5 M
Gal-Yam et al. 2009
(SN 1987A x 70)
![Page 35: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/35.jpg)
Massive Star Origin ?
Pop III : Mass Accretion ? (e.g. Ohkubo+ 2009)
M ~ 40 - 140 M
M ~ 140 – 300 M
M > 300 M
(dM/dt ??)Stellar Mergers in Dense Star Clusters?
(e.g., Ebisuzaki+)
![Page 36: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/36.jpg)
Pop III Stars: Mass Accretion Pair-Instability (140-300 M) or Core-Collapse
Ohkubo et al. (2009)
Accretion Final Mass
1 M
![Page 37: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/37.jpg)
Ohkubo et al. (2009)
Pop III Stars: Mass Accretion Core Collapse (40-140 M) LSN & GRB ?
Accretion Final Mass
1 M
![Page 38: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/38.jpg)
M = 50M
M =100M
E51 = 30
E51 = 30
E51 = 100
E51 = 100
Umeda & Nomoto
56Ni 56Ni
56Ni56Ni
Log (Mass Fraction)
Log (Mass Fraction)
Mr
Mr Mr
Core-CollapseSN Models
![Page 39: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/39.jpg)
• M (ms) = 100 M 270 M
• M (C+O core) = 43 M 121 M
• M (ejecta) = 39 M 121 M
• E (kin) = 3.3 E52 erg 7E52 erg• M (56Ni) = 6.1 M 9.8 M
• LC: rise time = 52 - 85 days 150 days• Jet-induced Explosion Aspherical Hypernova GRB?
Models for Luminous SNeCore-Collapse PISN
![Page 40: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/40.jpg)
PISN vs. Core-Collapse :SN Ic 2007bi, SN IIn 2006gy
Moriya et al.
![Page 41: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/41.jpg)
SN Ibc 2007bi (core-collapse Hypernova)
Moriya et al.
![Page 42: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/42.jpg)
Photospheric Velocity (SN 2007bi)
Moriya et al.
![Page 43: Diversity of Supernova-Hypernova Propertiesinoue/GRB2010web/...The Final Fates of Single Stars • M < 0.08 M Brown Dwarf • 0.08 -- 0.46 M He White Dwarf • 0.46 -- 8 M C+O White](https://reader035.vdocuments.us/reader035/viewer/2022071609/61480510a830d0442101cfe5/html5/thumbnails/43.jpg)
Extremely Luminous SupernovaePair Instability SN ?Core-Collapse Hypernovae (Pop III GRB?)Circumstellar Interaction ?
Mass loss ?Mass Accretion ?Stellar Mergers ?
Fallback SN ? Low Mass SN?non-SN GRB & Metal Poor Stars
Extremely Faint Supernovae