Determination of the large-scale and meridional flows in the deep convection zone by time-distance helioseismology
ROSES ID: NNH08ZDA001N Selection Year: 2009
Program Element: Focused Science Topic
Principal Investigator: Alexander Kosovichev
Affiliation(s): Stanford University
Project Member(s):
Scherrer, Philip H. Co-I/Institutional PI HEPL
Zhao, Junwei Collaborator null
Hartlep, Thomas Collaborator NASA Ames Research Center
Parchevsky, Konstantin Collaborator Stanford University
Mansour, Nagi Nicolas Consultant NASA Ames Research Center
Summary:
We propose a focused investigation with the main goal of
detecting the return meridional flow and measuring the
properties of deep large-scale flows associated with formation
of active regions. Determination of the large-scale and
meridional flows in the solar convection zone is crucial for
understanding and modeling the solar dynamo and making sort-
and long-term predictions of solar activity. There is no doubt
that the large-scale and meridional flows play a significant
role in the dynamo operation and in the generation of active
regions. The local helioseismology inferences have revealed a
complicated dynamics associated with the meridional flux
transport and evolution of active regions in the upper
convection zone. It has been shown that these inferences have a
profound effect on the flux-transport mechanism. However, the
effects of these flows on the properties of the solar dynamo
and active region formation are far from understanding. For
this it is particularly important to determine the structure
and dynamics of these flows in the deep convection zone
including the tachocline where the solar magnetic fields are
believed to be generated and organized. This problem is
difficult because the deep flows are relatively weak, and their
helioseismic signals are difficult to extract from the noisy
oscillation data contaminated by the surface magnetism effects.
For tuning of the helioseismic measurements and verification
and testing of the results we propose to use numerical
simulations of stochastically excited acoustic waves in 3D MHD
models of the whole Sun, and use the simulation data for
developing, the helioseismic techniques. This work includes a
thorough investigation of systematic errors and uncertainties,
including potential contamination by the surface magnetism
effect.
Publications:
Performance Year | Reference | Investigation Type | Actions |
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1 | Pipin, V. V.; Kosovichev, A. G.; (2011), Mean-field Sol...
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Presentations:
Performance Year | Reference | Actions |
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1 | Kosovichev, A.; Zhao, J.; Sekii, T.; Nagashima, K.; ...
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1 | Nagashima, K.; Zhao, J.; Kosovichev, A. G.; Sekii, T...
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1 | Hartlep, Thomas; Roth, M.; Doerr, H.; Zhao, J.; Koso...
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