SLIDE 1
動的な太陽大気モデルの系譜
磁気大気の活動性の起源
加藤 成晃（NAOJ）
1 太陽と恒星の物理学 2011/12/26-28
動的な太陽大気モデルの系譜
磁気大気の活動性の起源
加藤 成晃（NAOJ）
1
Okamoto et al. (2007) Ca II H
太陽と恒星の物理学 2011/12/26-28
NAOJ - - PowerPoint PPT Presentation
NAOJ - - PowerPoint PPT Presentation
NAOJ 2011/12/26-28 1 NAOJ
SLIDE 2
SLIDE 3
概要
動的な太陽大気モデリングの系譜 今後の太陽大気モデリングの課題 新しい試みの紹介
2 太陽と恒星の物理学 2011/12/26-28
SLIDE 4
Toward Realistic
Modelings of Solar Atmosphere
Heat conduction along field lines from corona Radiative Transfer
- LTE + Non-LTE
- Opacity
✓
Continuum
✓
Lines
- Ionization
✓
Collisional excitation
✓
Photo-ionization
Magneto-convection
- Radiative cooling
- EOS
Schrijver 2001
z [Mm] 1 2 6000 K 106 K 105 K
太陽と恒星の物理学 2011/12/26-28 3
SLIDE 5
Toward Realistic
Modelings of Solar Atmosphere
Heat conduction along field lines from corona Radiative Transfer
- LTE + Non-LTE
- Opacity
✓
Continuum
✓
Lines
- Ionization
✓
Collisional excitation
✓
Photo-ionization
Magneto-convection
- Radiative cooling
- EOS
Schrijver 2001
z [Mm] 1 2 6000 K 106 K 105 K
太陽と恒星の物理学 2011/12/26-28
Basic equations
Solar “ingredients”:
3
SLIDE 6
What physics need to be included in numerical simulations?
2-D/3-D domain ranging from convection zone to corona
✓
Energy flow from convection zone to corona
Energy balance
✓
Shock dissipation (High spatial resolution)
✓
Conduction (Short time-scale)
✓
Radiation in strong lines from H, Ca, Mg, He (Non-LTE 6-12 levels per element) and in many weak lines (many frequency bins)
Radiation transfer
✓
Non-locality, Frequency integration, and Scattering
MHD
✓
Reconnection, high Alfven velocity (Shor time-scale)
✓
Chromosphere is mostly neutral (multi-fluid)
Plasma
✓
Need to solve rate equation for Hydrogen ionization
✓
non-Maxwellian distribution functions need kinetic modelling
Can we do this?
- In principle, yes
- 20 km resolution, 50 Mm box, NLTE H+Ca+He
+Mg: 6 million years on 5000 CPUs for one hour of solar time
- In practice, no
by M. Carlsson
SLIDE 7
Current understanding of the dynamics in Quiet Region
Convection zone Photosphere Chromosphere Corona
石川 岡本 勝川
太陽と恒星の物理学 2011/12/26-28 5
Conventional picture
SLIDE 8
Canopy Sub-canopy Canopy β=1 Magnetic Sub-magnetic
太陽と恒星の物理学 2011/12/26-28
Convection zone
Current understanding of the dynamics in Quiet Region
Modern picture
6
τ500=1
SLIDE 9
Magneto-convection simulation
“fly” movie by Mats Carlsson & Bob Stein (Stagger code)
7
G-band
SLIDE 10
Magneto-convection simulation
“fly” movie by Mats Carlsson & Bob Stein (Stagger code)
7
G-band B-field
SLIDE 11
Magneto-convection simulation
“fly” movie by Mats Carlsson & Bob Stein (Stagger code)
7
G-band B-field Height where tau=1
SLIDE 12
Magneto-convection simulation
“fly” movie by Mats Carlsson & Bob Stein (Stagger code)
7
G-band B-field Height where tau=1
SLIDE 13
3-D Dynamical Modeling of Network/Internetwork Region
- M. Carlsson by using BIFROST
(Gudiksen et al. 2011)
太陽と恒星の物理学 2011/12/26-28 8
SLIDE 14
3-D Dynamical Modeling of Network/Internetwork Region
- M. Carlsson by using BIFROST
(Gudiksen et al. 2011)
太陽と恒星の物理学 2011/12/26-28 8
SLIDE 15
3-D Dynamical Modeling of Network/Internetwork Region
- M. Carlsson by using BIFROST
(Gudiksen et al. 2011)
太陽と恒星の物理学 2011/12/26-28 8
SLIDE 16
Comparison between
Models and Observations
太陽と恒星の物理学 2011/12/26-28 9
RMHD Model atmosphere Detailed Radiation transfer Simulated intensity Reconstructed atmosphere Inversion Observations
SLIDE 17
Ca II H-line formation
in 1-D Non-LTE Model atmosphere
by Carlsson & Stein 1992, 1994, 1995, 1997
太陽と恒星の物理学 2011/12/26-28 10
勝川
SLIDE 18
Ca II H-line formation
in 1-D Non-LTE Model atmosphere
by Carlsson & Stein 1992, 1994, 1995, 1997
太陽と恒星の物理学 2011/12/26-28 10
SLIDE 19
Current issues
for modeling of Solar atmosphere
Leenaarts et al. 2011
太陽と恒星の物理学 2011/12/26-28 11
Total heating rate ad-hoc heating rate Total Radiative heating rate Compression work What’s minimum temperature? Heating Cooling
Martinez-Sykora, De Pontieu, Hansteen 2012
SLIDE 20
Chromosphere/Corona heating
“Energy flows”
太陽と恒星の物理学 2011/12/26-28 12
Excitation Propagation Dissipation
SLIDE 21
Discovery of Excitation of Slow-modes
YK, Steiner, Steffen, Suematsu (2011) by using CO5BOLD white contour: Magnetic field line, Arrows: velocity White & Black curve: Optical surface
Tgas
Nx=400 Nz=165
13 太陽と恒星の物理学 2011/12/26-28
SLIDE 22
4000 4400 4800 5200 x [km] time = 15.1 min 4000 4400 4800 5200 x [km]
- 1200
- 1000
- 800
- 600
- 400
- 200
200 z [km] time = 12.5 min 4000 4400 4800 5200 x [km] time = 13.8 min 4000 4400 4800 5200 x [km] time = 16.4 min
- 10
- 5
5 10
(b) (a)
Vz [km s-1]
12 13 14 15 16 17 18 Time [min]
- 1200
- 1000
- 800
- 600
- 400
- 200
200 z [km] downdraft
<Vz>skin [km s-1]
12 13 14 15 16 17 18 Time [min] downflow shock upflow
<Vz>core [km s-1]
Downflow Upflow <!>core = 1 <">core = 1 core skin skin 14 Spatially averaged vertical velocity in the skin region
EXCITATION OF SLOW-MODE & SHOCK
YK, Steiner, Steffen, Suematsu (2011) Spatially averaged vertical velocity in the core region 太陽と恒星の物理学 2011/12/26-28
SLIDE 23
4000 4400 4800 5200 x [km] time = 15.1 min 4000 4400 4800 5200 x [km]
- 1200
- 1000
- 800
- 600
- 400
- 200
200 z [km] time = 12.5 min 4000 4400 4800 5200 x [km] time = 13.8 min 4000 4400 4800 5200 x [km] time = 16.4 min
- 10
- 5
5 10
(b) (a)
Vz [km s-1]
12 13 14 15 16 17 18 Time [min]
- 1200
- 1000
- 800
- 600
- 400
- 200
200 z [km] downdraft
<Vz>skin [km s-1]
12 13 14 15 16 17 18 Time [min] downflow shock upflow
<Vz>core [km s-1]
Downflow Upflow <!>core = 1 <">core = 1
Downflows Shock wave Magnetic pumping
14 Spatially averaged vertical velocity in the skin region
EXCITATION OF SLOW-MODE & SHOCK
YK, Steiner, Steffen, Suematsu (2011)
Downdrafts
Spatially averaged vertical velocity in the core region 太陽と恒星の物理学 2011/12/26-28
SLIDE 24
まとめ
動的な太陽大気モデリングにはRMHDが必要不可欠！
磁気大気：Canopyなどの複雑な磁場構造によって大気構造が決まっている Ca II H-lineの放射メカニズムには衝撃波からの複雑な寄与がある
実用的なRMHD計算技術の開発が必要
Opacity table/Realistic EOS 高速化
定常一次元”平行平板”大気モデルについて
ただし「動的な太陽大気モデル」から「定常一次元的な大気モデル」を再構 築することは、太陽と恒星の理論と観測の両方の面で重要かも知れない。
15 太陽と恒星の物理学 2011/12/26-28