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Kosovichev fit Kosovichev (1996; ApJ 469, L61)
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Inferred rotation rate
Fits to tachocline
Kosovichev fit
Kosovichev (1996; ApJ 469, L61)
Kosovichev fit
Rotational inversion
Tests on artificial data
Charbonneau et al. (1999; ApJ 527, 445)
Analysis of LOWL data
Charbonneau et al. (1999; ApJ 527, 445)
Analysis of GONG and MDI
Basu & Antia (2003; ApJ 585, 553
The base of the convection zone Model S
Model 31
Model 31:
Subadiabatic overshoot
(Rempel 2004; ApJ 607, 1046)
Oscillatory signal from base of convection zone
Monteiro et al. (1994; A&A 283, 247)
Analysis of oscillatory signal
Zonal flowsRotation rate - average value at solar minimum
Vorontsov et al. (2002; Science 296, 101)
Tachocline oscillations
See Howe et al. (2000; Science 287, 2456)
● GONG-RLS
▲MDI-RLS
∆ MDI-OLA
Basu & Antia (2001; ApJ 324, 498)
Jets in the tachocline?
Dipakti, Gilman, C-D, Thompson
Jets in the tachocline?
Observations of tachocline jets
(for inclusion in Monday morning discussion on observations lead by Christensen-Dalsgaard)
JETS IN THE SOLAR TACHOCLINE AS DIAGNOSTICS OF GLOBAL MHD
PROCESSES THERE
J. Christensen-Dalsgaard, Univ. of Aarhus, DenmarkT. Corbard, Obs. de la Cote d’Azur, France
M. Dikpati, HAO/NCAR, USAP. A. Gilman, HAO/NCAR, USA
M. J. Thompson, Univ. of Sheffield, UK
Inversion of rotational splittings from GONG Inversion of rotational splittings from GONG observations 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
Results from helioseismology 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.
Results from helioseismologyhelioseismology (continued)
First 2 panels are average solution and error for 1996,
used as reference. Remaining panels show difference between
yearly averages and 1996.
Results from helioseismology (continued)
R L S O L A
Jet a
mp l
itude
(nH
z)
Jet a
mpl
itude
(nH
z)
Dep
th (
R )
Dep
th (
R )
Latit
ude
(deg
ree)
Lati t
u de
(de g
r ee)