Core Collapse And Supernova Explosion Of Massive Star Having Magnetic Field Inclined To The Rotation

1
Core Collapse And Supernova Explosion Of Massive
Star Having Magnetic Field Inclined To The
Rotation Axis

• Hayato Mikami (Chiba Univ.)
• Collaborators Yuji Sato(Chiba Univ.),
• Tomoyuki Hanawa(Chiba Univ.),
• and Tomoaki Matsumoto(Hosei Univ.)

2
Introduction

• Type-II supernovae
• Asymmetric explosions
• 2D MHD simulation(Sawai et al. 2004, Ardeljan et
  al. 2005)
• The 3D effect by the magnetic field inclined to
  the core rotation axis
• Magnetic field configuration
• Direction of outflow
• Dependence on the initial O and B

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Initial model

• ?0 6.8109 g cm-3
• 15 Mo model (Woosley et al. 2002)

6000 km
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Initial model

• ?0 6.8109 g cm-3
• O0 0.15 - 1.2 rad s-1
• Differential rotation

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Initial model

• ?0 6.8109 g cm-3
• O0 0.15 - 1.2 rad s-1
• B0 0.25 - 4.01012 G
• Dipole-like
• Uniform near the central region

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Initial model

• ?0 6.8109 g cm-3
• O0 0.15 - 1.2 rad s-1
• B0 0.25 - 4.01012 G
• f0 60

f0
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Parameters

• Initial rotation O0
• Initial magnetic field B0

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The calculation method

• Ideal MHD equations
• EOS(Takahara Sato, 1984)
• The phenomenological parametric
• P Pthermal Pcold
• Pcold K?G
• Nested grid method
• Roe method modified with the care for the
  Carbuncle instability
• Numerical Viscosity to Care the Carbuncle
  Instability (Hanawa,11/3)

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Parameters
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Overview
230 ms
t0 ms
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Overview
The next movie
Core collapse (189 ms)
After bounce (41 ms)
Jets
206 ms
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3D movie
The initial parameters O0 1.22 s-1 B0
3.041012 G
400 km
O0
B0
lines - Magnetic fields - proto
neutronstar ( ? gt 1014 cm s-1 )
- outflow ( vr gt 109 cm s-1 ) 185
ms lt t lt 230 ms
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Time evolution of Energy (Rlt40 km)
Eg
Ecold
Ethermal
Ek
Emag
Jets
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Emag was stored on R10 60 km
206 ms
Enhanced by the core rotation
Emag (erg)
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Jet launched at R60 km
206 ms
Jets
109 cm s-1
60 km
NS
10 km
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2D movie (187 lt t lt 230 ms)
187 ms
O0
B0
B0
O0
200 km
40 km
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Layers of neutral sheets
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Jets launched from R60 km
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Dependence on the initial O
Fast O0 produced fast jet
Fast O0 model
Faster
Slow O0 model
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Dependence on the initial B
Strong B0 produced fast jet.
Strong B0 model
Faster
Weak B0 model
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Conclusion

• Neutral sheets new feature in 3D
• Emag is stored on the sphere of R10 and 60 km.
• Jets
• Direction of jets is along the rotation axis.
• Jets are launched from R60 km.
• Fast O0 produce fast jets.
• Strong B0 produce fast jets.