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image: http://chandra.harvard.edu/photo/2006/casa/
Toward high-resolved hydrodynamic Simulations of Supernova remnants such as Cas A, Tycho ..
Masaomi OnoKyushu University
TV meeting2009.07.24
1
Contents
• Introduction• Antecedent studies• Calculation toward Tycho SNR– Initial condition–Method–Results
• Future prospects
2
Introduction
3
SNR observations 1 (Tycho)
• X-ray image– Red: Fe L-shell– Green: Si K-shell– Blue: high energy
• 1 : 0.93 : 0.70(BW:CD:RS)
4
Warren et al. 2005
Chandra X-ray image
• Spectrum– Featureless– Ejecta
5
Warren et al. 2005
SNR observations 3 (Tycho)
• Ion X-ray emmitions
• Ion temperature(1-3)×1010 K
6
Furuzawa et al. 2009
SNR observations 3 (Tycho)
Antecedent studies
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Thermal X-ray emission from shocked ejecta in Type Ia SNR 1
• Explosion mechanisms– DET– SCH– DEF– DDT– PDD
8
Badenes et al. 2003; Badenes et al. 2005
Plasma model & Ionization calculation9
Badenes et al. 2003; Badenes et al. 2005
Calculated synthetic spectrum
• Hamilton & Sarazin code + XSPEC software package
10
Badenes et al. 2003; Badenes et al. 2005
11
Wheeler, Maund & Couch 2008
Proposed jet direction Proper motion of compact object
Holes
The shape of Cas A 1
The shape of Cas A 2
• High-resolution hydrodynamic simulation– FLASH Code (Fryxell et al. 2000)
12
Wheeler, Maund & Couch 2008
Jet
13
Calculation toward Tycho SNR
Initial condition
• Carbon deflagration model (W7)– Nomoto, Thielemann & Yokoi 1984• Density, temperature, chemical composition
radial velocity
• Ambient medium– ρAM = ~ 10-25 g cm-3 (1 個 cm-3)
– T = 103 K
14
Initial chemical composition15
Thielemann, Nomoto & Yokoi 1986
Method & input physics
• Hydrodynamic simulation– Cede: ZEUS-2D– EoS• Ideal gas + radiation (optically thick)• P = K ργ, e = P / (γ - 1) (optically thin)• τ = ∫ κ ρ dr = 2/3 (κ: electron scattering)
– α-network (Müller 1986)• 4He, 12C, 16O, 20Ne, 24Mg, 28Si, 32S, 36Ar, 40Ca,
44Ti, 48Cr, 52Fe, 56Ni
16
Density17
Energy density18
Temperature19
Density profile20
Radial velocity profile21
Mass fraction22
Problems
• Oscillation– Rezoning
& mapping ?
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Future prospects
High-resolution MHD simulation
• AMR (Adaptive Mesh Refinement)– Berger & Oliger 1984; Berger & Colella 1989
25
Magnetic fieldAMR (3D) Nucleosynthesis+ +
How we achieve the aim ?
Hydrodynamic Codes• FLASH– PARAMESH AMR package– 3D, MPI, small nuclear reaction network – Two MHD units (8wave or USM)– Ionization unit (NEI)
• ZEUS-MP– 3D, MPI, magnetic field (MOC-CT)
radiation HD (FLD)
26
ZEUS-MP + AMR + Network v.s. FLASH ?
FLASH with magnetic field
• On the origin of asymmetries in bilateral supernova remnants– 3D MHD simulations by FLASH code
27
Orlando et al. 2007
Initial distributions of density & magnetic field
Synthetic radio emission28
Orlando et al. 2007
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