1. Giant Convective Cell 観測と理論 太陽雑誌会（２００５．３．６） 北井

2. 概要 はじめに 理論の紹介 GLOBAL-SCALE TURBULENT CONVECTION AND MAGNETIC DYNAMO ACTION IN THE SOLAR ENVELOPE A. S. Brun, M. S. Miesch, J. Toomre (Ap J, 614:1073–1098, 2004) 観測の紹介 PHOTOMETRIC SEARCH FOR SOLAR GIANT CONVECTION CELLS W.-H. Chiang, L.D. Petro, P.V. Foukal (Solar Phy. 110, p129,1987) THE DETECTION OF GIANT VELOCITY CELLS ON THE SUN J.G. Beck, T.L. Duvall, Jr, P.H.Sherrer, and J.H. Hoeksema( Soho6/GONG98 Workshop, 1998) 62-DAYS AROUND THE SUN: A SEARCH FOR SUPERGRANULAR EVOLUTION AND GIANT CELLS L.H. Strous and G.W. Simon ( ASP conf. series 140, 161, 1988) SMART データによる観測計画案

3. Giant Convetive Cell

5. GLOBAL-SCALE TURBULENT CONVECTION Brun’s Numerical Simulation 3D spherical shell Anelastic MHD Equation Neglection of Sound speed :infinite Thermodynamic Quantities Sherical symmetiric component +fluctuation D : Viscous tensor

6. GLOBAL-SCALE TURBULENT CONVECTION Brun’s Numerical Simulation Boundary condition Shell 0.72-0.98 Solar Radius

7. GLOBAL-SCALE TURBULENT CONVECTION Brun’s Numerical Simulation

10. 観測（１） Chiang et al Kitt Peak Search for large-scale temperature fluctuation Photometry atλ525.6nm by 512-diode Reticon through spectrometer Spatial scan perpendicular to the solar rotation axis 15days, 4 N-zone + 4 S-zone scan

11. 観測（１） Chiang et al

12. Temperature Fluctuation RMS = 0.33K ( 0.023%) Spatial scale 80-240Mm ⇒ Detection of Giant Cell ? （ Simulation predicts ΔT ≒１ K)

13. 観測 (2) Beck et al SOHO/MDI Doppler data Daily averaged frame / 1440 frames taken in 1-min cadence Low resolution data (12deg square) May 1996-Sep 1997 : 505days time series Medium resolution data ( 32min square ) May 1996-Nov 1997 : 576days time series

14. 観測 (2) Beck et al (Low Resolution) 27-days long-lived feature Lifetime : 4months V(horizontal) : 3.6m/s L(horizontal) : 44deg

15. 観測 (2) Beck et al (Medium Resolution) Velocity amplitude : 3.2m/s Cell : Horizontally elongated ( 56 deg x 7 deg ) ⇒ Detection of Giant Cells

16. 観測（３） Strous & Simon 62-day time-series of full- disk SOHO/MDI Dopplergrams obtained at a one-minute cadence Subtraction of background Doppler signal (5-degree polynomial fitting) Spatial smoothing ( 85” and 171” ) Movie Watch ⇒ No giant cells detected

17. 観測（３） Strous & Simon Feature Tracking ( SG cells as tracers )

18. 観測（３） Strous & Simon Result Unexplained horizontal velocity field of 30m/sec ⇒ Detection of Giant cell inconclusive

19. Hida-FMT での解析

23. SMART での解析 Full-disk Hα wing image LCTM ( Even-Odd test, Reverse test ) Tracer : Supergranulation Spatial resolution : 0.5” ( FMT 4”) Merit : Tracers all over the disk Deficit : Interrupttion by nights

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