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ハイパーノバとブラックホーハイパーノバとブラックホールル
Hypernovae and Black HolesHypernovae and Black Holes
野本憲一 (Nomoto, Ken’ichi)
前田啓一 (Maeda, Keiichi)
東京大学大学院理学系研究科天文学専攻University of Tokyo, School of Science, De
partment of Astronomy
SN 1998bw
=
SN 1987A
E ~ 30×1051ergs E ~ 1×1051ergs
SNe Ic SNe IInSN GRB SN GRB
1998bw 980425 1997cy 970514
1997ef 971115 1999E 980910
1999as 1988Z
2002ap 1999eb 991002
1997dq
1998ey
1992ar
Hypernova CandidatesEkinetic > (5-10)×1051ergs
SN 1998bw
GRB 980425
• Observations: Spectra, Light Curves– Progenitors, Energetic, M(56Ni)
• The properties of Hypernova Explosions– Features unexpected by spherical models– Black Hole Formation
• Jet-Driven Explosion Model– Explains the above features?– Predictions
• Evolution of the central black hole. • Nucleosynthetic features (e.g., 56Ni)• Gravitational wave (?) - Optical Display - Abundances
Possible Gravitational Wave from Hypernovae?
• MBH ~4M
• Low Viscosity Case M (R<300km)– 0.0033 M
• High Viscosity Case – 2.21 M– j~1017 cm2s-1
• Self-Gravity• Large EROT/|EGRAV|
Macfadyen et al. 1998
Bar Mode Instability?
R ~100km at Bounce
M~1M
J Conserve
j~1016cm2s-1
R ~100kmMDISK~2M
J Conserve
j~1017cm2s-1
h~4×10-20 (1Mpc/D) (j/1017cm2s-1) (M/M) (f/1000Hz)
f~1000 (j/1017cm2s-1) (100km/R)2 e.g., Fryer et al.2002
SN at 10Mpc (1SN/year); f~100 Hz, h~4×10-
23
HN at 100Mpc (1HN/year); f~1000 Hz, h~8×10-22
Ia
Ic
Ib
94I
97ef
98bw
HeCaO
SiII
Hyper -novae
Spectra of Supernovae & Hypernovae
Hypernovae : broad features blended lines “ Large mass at hi
gh velocities”
Ic: no H,
no strong He,
no strong Si
Light Curves of Supernovae & Hypernovae
Light Curve Broadness
SN1998bw >> SN1994I
Ejected Mass
SN1998bw >> SN1994I
Progenitor’s Mass
SN1998bw >> SN1994I
Parameters [Mej, E, M(56Ni)]
Si
C+O
He
H-rich
MC+O
FeCollapse
56Ni
56Co
56
Fe
Mms/M MC+O/M
~ 40 13.8
~ 35 11.0
~ 22 5.0
Light Curve Spectra
~ [dyn • diffusion]1/2
~ • RV R c
Mej1/2
½Mej¾E -¼
E Mej3
E Mej
CO Star Models for SNeIc
56 Ni
Spectral Fitting: SN1997ef
Model
Normal SN
Small Mej
Too Narrow Features
Spectral Fitting: SN1997ef
Model
Hypernova
Large Mej
Broad Features
Progenitors’ Mass – E – M(56Ni)
Most Stars (>25M) explode as Hypernovae?
• The Contribution of Hypernovae is Large.– Hypernovae are Not so Rare Events.
Distribution of HNe
Distance – Absolute Magnitude of SNe Ib/c
10 100 Mpc
• 1 HN per 1 year in R<100Mpc.
• 1 SN per 1 year in R<10Mpc.
Hypernova Rate
• Large Fraction of Massive O (or He) Star with M>20M Explodes as Hypernovae. Depending on Binary Evolution?
Local SN Rate (SN/100yr/1010L) h=H0/100
Ia Ib/c II All
0.36±.11h2 0.14±.07h2 0.71±.34h2 1.21±.36h2Corrected1)
Observed2) 111 18 54 183
1)Cappellaro et al. 99, 2)Richardson et al. 01
HNIb/c
SNIb/c= 3(+1+2)/18
~ 0.15 – 0.3
N(20M-50M)
N(8M-20M)~ 0.3 (Salpeter IMF)
Properties of Hypernova Explosions
(1) Deviation from spherical explosion models(2) Black hole formation
1) Asphericity in Core-collapse SNe (in general)
HST Image of SN1987A
Wang et al. 2002
Optical Spectropolarimetry of
SNe 1993J, 1996cb, Wang et al. 1999
SN1987A: Asymmetrical, but not spherical, ejecta
Optical Polarization in core-collapse SNe > 0.5 %(in SNe Ia < 0.2 - 0.3%)
1998bw
1997ef
2002ap
1998bw
1997ef
2002ap
High Density
Spherical Hydro Model
Low Density
(Vacuum)
2) Light Curves of Hypernovae
Maeda et al. 2003, ApJ, submitted
ObserverExpansion
Fe
O
Spherical
FeII] 5200A
[OI] 6300A
Observation
FWHM
3) Late time spectra of SN1998bw
Line Width Inversion between Fe and O
Broader Fe lines than O lines in the observations.
Low velocity O-rich Matter: SNe1998bw, 1997ef
56Fe
16O
Spherical
Aspherical
15 deg
FeII] 5200A
[OI] 6300A
Maeda et al. 2002
Observation
Interpretation as an Aspherical explosion
• Enhancement of O,Mg,Si,S,Ti by a factor of 6-10.
Israelian et al. 1999
Abundances in Nova Sco
-0.5
0
0.5
1
1.5
N O Mg Si S Ti Fe
[X/H
]
SN matter
BH
[X/H]=log10(X/H)-log10(X/H)
4) BH Formation
Hypernova model for the formation of the BH in Nova Sco
Abundance in Nova Sco
0
0.2
0.4
0.6
0.8
1
He C O Ne Mg Si S Ca Ti Fe
[X/H
]
E51=30
BH mass in the model
4.8M at the explosion
5.4M now (Post SN)
SN
BH
MMS=40M, MHe=16M, E51=30
MBH at the explosion ~ 5M
Black hole formation with a Hypernova explosion.Podsiadlowski et al. 2002
The properties of hypernova explosions
• High velocity material (Fe)• Low velocity & high density material (O)
– Contrary to conventional spherical models.
• forms a black hole, but explodes with large E51 (= E/1051ergs > 10).– Black hole formation does not always leads to
a failed supernova.
Do jet-induced explosions satisfy these conditions?
16MHe (MMS=40), 8M
He (MMS=25), (Nomoto&Hashimoto 1988)
MRem0 1.0 – 3.0M
Ejet = Mc2 , 0.01
Model: Jet-induced Explosion
Newtonian Gravity
Radiation+ Pairs15o
Postprocessing
222 isotopes (Tielemann et al.)K. Maeda, in preparation
Hydrodynamics
Collimated jets (Z) + Bow shock (All direction)
M Lateral expansion
Radial Velocity/cLog (Density[g cm-3])
R/1010cm
Hydrodynamics (Center)
Accretion from the side
Continue to accrete, MBH
Radial VelocityDensity
R/1010cm
0.7 s
1.5 s
E51=11, MBH(final)=5.9M, M(56Ni)=0.11MOutflow
Inflow
R/1010cm
Density Distribution
Jet (z) (E51=11)
Jet (R)
Sph (E51=10)
Sph (E51=1)
High density core at the central region
High velocity material along z
Growth of a central remnant
Time (sec)
MBH
20 400
4
8 Inefficient Jet
efficient Jet
MREM can be ~ 5 – 10M, starting from 1.5 – 3M.
Still a strong explosion follows (E51>10).
A hypernova with a stellar mass black hole (X-ray Novasco; Large Si,S with black hole formation).
Final Remnants’ masses and Kinetic Energies
• A more massive star makes a more energetic explosion (As seen in ‘Hypernova Branch’).
11
6.9
1.9
5.9
E51=E/1051ergs MBH(M)
Peak Temperature & Density
• High T + Low Material are preferentially ejected.
R
Z
R
Z
Ejected
Accreted
T/109K
0
4
8
Log(Density[g cm-3])864
Spherical
Ejected Accreted
High Velocity FeLow Velocity O
6
4
2
02 4 6
Vz (/109cm s-1)
0.5
0.1
0.01
E51(=E/1051ergs)=10, MREM=6M, M(56Ni)=0.1M
16O56Ni(56Fe)
Fe, O Distribution
Vr
Relation in MREM and M(56Ni)
(M)
(M)
L Op
tica
l
Efficient
e.g., rotation
inefficient
40M
20M
GW: GW:
Fe
MnO
Zn
Velocity Inversion of isotopes
V(Fe) > V(O), V(Zn) > V(Mn)
Spherical; Zn Fe Mn O
T , Inner (smaller V)
Ejection of heavier isotopes with higher V
Prediction
Jet (Z) Jet (R)
Spherical Jet (all direction)
O Fe and heavier
Spherical, 1052ergs, 0.1M Ni
Jet-Driven, 1052ergs, 0.1M Ni
O, MgMn
Co, Zn
Abundances in the whole ejecta
Possible Contribution to the early Galactic Chemical Evolution
Jet model: [Zn/Fe] ,[Mn/Fe]
Agrees with the abundances in old stars.
Past
[X/Y] = log(X/Y) – log(X/Y)
More Massive Star
-1
-0.
5
0
-1
-0.
5
0
[S/Si]
-0.6
-
0.4
-0
.2
0
-0.6
-
0.4
-0
.2
0
[Si/O]
40M25M
MBH/M
0 1 2 30 5 10
56Ni
S Si O
Accretion
Sph
Jet
Accretion
[S/Si],[Si/O]
0 5 10 0 1 2 3
MBH/M-0.2
0
0
.2
0
.4
-0.2
0
0
.2
0
.4
-1.4
-
1.2
-1
-0
.8
-1.4
-
1.2
-1
-0
.8
40M25M
[Mg/O]
[C/O]
O,Mg C
Accretion
Sph
Jet
Accretion
[Mg/O] ,[C/O]
Summary• The studies on hypernovae indicate;
– Velocity inversion of Fe and O – Dense core– Black hole formation
• Jet-induced explosions satisfy the above condition!– Blow up heavy isotopes (e.g., Fe, Zn) to the surface.– A black hole grows, with an energetic explosion.
• Possible site of gravitational wave emission?• Depending on angular momentum, HNe may be able to be detect
ed more easily than normal SNe.
– MBH efficiency of the jets (e.g., rotation?)
– MBH ( inefficient Jets) LOpt
– MBH Abundances (e.g., MBH [S/Si], [O/C] )