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Published byTheodora Atkinson Modified over 9 years ago
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Inferred rotation rate
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Fits to tachocline
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Kosovichev fit Kosovichev (1996; ApJ 469, L61)
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Kosovichev fit
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Rotational inversion
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Tests on artificial data Charbonneau et al. (1999; ApJ 527, 445)
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Analysis of LOWL data Charbonneau et al. (1999; ApJ 527, 445)
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Analysis of GONG and MDI Basu & Antia (2003; ApJ 585, 553
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The base of the convection zone Model S Model 31 Model 31: Subadiabatic overshoot (Rempel 2004; ApJ 607, 1046)
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Oscillatory signal from base of convection zone Monteiro et al. (1994; A&A 283, 247)
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Analysis of oscillatory signal
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Zonal flows Rotation rate - average value at solar minimum Vorontsov et al. (2002; Science 296, 101)
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Tachocline oscillations See Howe et al. (2000; Science 287, 2456) ● GONG-RLS ▲ MDI-RLS ∆ MDI-OLA Basu & Antia (2001; ApJ 324, 498)
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Jets in the tachocline? Dipakti, Gilman, C-D, Thompson
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Jets in the tachocline?
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Observations of tachocline jets (for inclusion in Monday morning discussion on observations lead by Christensen-Dalsgaard)
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JETS IN THE SOLAR TACHOCLINE AS DIAGNOSTICS OF GLOBAL MHD PROCESSES THERE J. Christensen-Dalsgaard, Univ. of Aarhus, Denmark T. Corbard, Obs. de la Cote d’Azur, France M. Dikpati, HAO/NCAR, USA P. A. Gilman, HAO/NCAR, USA M. J. Thompson, Univ. of Sheffield, UK
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Inversion of rotational splittings from GONG observations Goal: determine rotation rate as function of latitude and distance from center Use individual 108-day data (three GONG months) and one year averages Inversion Techniques: OLA: Optimal combination of data to find localized averages of rotation rate, controlling also solution error RLS: Least-squares fit to data, regularized by minimizing also second derivative of solution
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Results from helioseismology First 8 panels show differences between individual three- GONG-months sets and the reference 1996 average, for 2002 (the year of the highest signal). Last panel repeats the difference for the yearly average for 2002.
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helioseismology Results from helioseismology (continued) First 2 panels are average solution and error for 1996, used as reference. Remaining panels show difference between yearly averages and 1996.
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Results from helioseismology (continued) R L S O L A Jet amplitude (nHz) Depth ( R ) Latitude (degree)
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