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Sarbani Basu Yale Unoversity

GONG 2010 - SoHO 24 A new era of seismology of the Sun and solar-like stars Aix-en-Provence, France. Sarbani Basu Yale Unoversity. GONG 2004 – SoHO 14 Helio- and Asteroseismology: Towards a Golden Future New Haven, CT, USA. The future is here!. GONG: Alive and well.

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Sarbani Basu Yale Unoversity

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  1. GONG 2010 - SoHO 24A new era of seismology of the Sun and solar-like starsAix-en-Provence, France Sarbani Basu Yale Unoversity

  2. GONG 2004 – SoHO 14Helio- and Asteroseismology: Towards a Golden FutureNew Haven, CT, USA

  3. The future is here!

  4. GONG: Alive and well

  5. And after years of waiting in anticipation

  6. We can actually do serious asteroseismology now!

  7. In fact, we find ourselves drowning in data.

  8. Sir Arthur Eddington in “The internal constitution of stars” (1926) “At first sight it would seem that the deep interior of the Sun and stars is less accessible to scientific investigation than any other region of the universe. Our telescopes may probe farther and farther into the depths of space; but how can we ever obtain certain knowledge of that which is being hidden behind substantial barriers? What appliance can pierce through the outer layers of a star and test the conditions within?”

  9. The questions have changed. Early concerns for helioseismology were the structure and dynamics of the Sun (the questions that we face in asteroseismology today). Current issues deal with more detailed (and more difficult!) phenomena.

  10. Local Helioseismology

  11. GONG 2010 Aix-en-Provence 3D Inversions Target Depth 1 Mm Target Depth 5 Mm

  12. How deep are Sunspots? Acoustic haloes: Surface effect? And what of the discrepancies?

  13. Wave-speed below sunspots • Results are inconsistent for depths > 2 Mm • For all methods and models, except TD: increased wave-speed for depths < 2 Mm.

  14. J. Zhao & HMI team A. Birch & D. Braun ridge filters yield near-surface outflows phase-speed filters yield near-surface inflows

  15. The question of solar activity and activity related changes Solar oblateness changes, radius does not. Will PICARD confirm this?

  16. Is there a 2nd solar dynamo?

  17. Do we really know the microphysics of stars? Could we please, please get our acts together and solve the solar abundance problem? When will the opacity measurement results be available? Please sir, could I have some more (equation of state calculations)?

  18. Hey, we can do asteroseismology now!

  19. Problems: Mode identification!

  20. Stellar activity in mode parameters? The case of HD49933

  21. GOLF 5.81 σ Model G modes? • Adding 5 g modes l=1 (n=-4, -6, -8, -9 , -10)

  22. On the evolution of the rotation of the young Sun (compared to Bouvier observations) and its present profile obtained for different initial rotation rates A: no braking light blue on left figure, B and C with braking (B: 20km/s on ZAMs navy blue on left figure, C: 50 km/s) and a transport of momentum including diffuive and advective terms, see poster Model-15 Turck-Chièze et al. ApJ 1st June 2010, 715, 1539

  23. And what is HMI up to? HMI Optics Package (HOP) Connector Panel Z Focal Plane B/S Fold Mirror Shutters Alignment Mech X Limb Sensor Y Oven Structure Detector (Vector) Michelson Interf. Lyot Filter CEBs Detector (Doppler) Vents Limb B/S Front Window Active Mirror Polarization Selector Focus/Calibration Wheels Mechanical Characteristics: Box: 0.84 x 0.55 x 0.16 m Over All: 1.19 x 0.83 x 0.29 m Mass: 39.25 kg First Mode: 63 Hz OP Structure Telescope Support Legs (6) Front Door

  24. Global Helioseismology Processing HMI Data Processing Data Product Science Objective Tachocline Internal rotation Ω(r,Θ) (0<r<R) Meridional Circulation Local Helioseismology Processing Filtergrams Internal sound speed, cs(r,Θ) (0<r<R) Differential Rotation Near-Surface Shear Layer Full-disk velocity, v(r,Θ,Φ), And sound speed, cs(r,Θ,Φ), Maps (0-30Mm) Activity Complexes Active Regions Carrington synoptic v and cs maps (0-30Mm) Sunspots Doppler Velocity Irradiance Variations High-resolution v and cs maps (0-30Mm) Observables Deep-focus v and cs maps (0-200Mm) Flare Magnetic Configuration Line-of-sight Magnetograms Flux Emergence Far-side activity index Magnetic Carpet Line-of-Sight Magnetic Field Maps Vector Magnetograms Coronal energetics Large-scale Coronal Fields Vector Magnetic Field Maps Solar Wind Continuum Brightness Coronal magnetic Field Extrapolations Far-side Activity Evolution Predicting A-R Emergence Coronal and Solar wind models IMF Bs Events Version 1.0w Brightness Images HMI Data Products and Objectives Magnetic Shear

  25. a) Spectrum of 8 hours of HMI Doppler data near disk center; b) Spectrum of 8 hours of MDI hi-res data (from 1996);

  26. Early HMI MagneticField Observations Magnetic Field Blos Mean FieldHMI – MDI – WSO

  27. Early HMI MagneticField Observations Frame of Vector Field Movie from Mar 29 SunspotK. Hayashi, R. Centeno Eliot, et al.

  28. Meridional flows from Fourier-Legendre decomposition

  29. Spectral Comparison: HMI V vs AIA 1700 (period 2)

  30. Dynamos and flows And in the case of massive stars, primordial fields will probably play a large role.

  31. Can we detect large scale flows?

  32. And what can we look forward to? • SONG: Definitely • PLATO: We really hope so! • Stellar Imager: • Solar Orbiter:

  33. Issues • Theory is lagging behind: how do we deal will waves in a dispersive magnetic medium? • Will we be able to detect deeper flows in the Sun? And do the flows look anything like the simulations show? • What is the best way to analyze (and model) current data?

  34. We shall meet again in Cairns, Australia, Nov 12-16, 2012

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