HELIOSEISMIC DETECTION OF DEEP MERIDIONAL FLOW

Journal Article · Sat May 01 04:00:00 EDT 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/714/1/960· OSTI ID:21448871

Gough, Douglas ^[1]

---

1. Institute of Astronomy and Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0HA (United Kingdom)

Steady meridional flow does not make any first-order perturbations to the frequencies of helioseismic normal modes. It does, however, Doppler shift the local wavenumber, thereby distorting the eigenfunctions. For high-degree modes, whose peaks in a power spectrum are blended into continuous ridges, the effect of the distortion is to shift the locations of those ridges. From this blended superposition of modes, one can isolate oppositely directed wave components with the same local horizontal wavenumber and measure a frequency difference which can be safely used to infer the subsurface background flow. But such a procedure fails for the components of the more deeply penetrating low-degree modes that are not blended into ridges. Instead, one must analyze the spatial distortions explicitly. With a simple toy model, we illustrate a method by which that might be accomplished by measuring the spatial variation of the oscillation phase. We estimate that by using this procedure, it might be possible to infer meridional flow deep in the solar convection zone.

• OSTI ID: 21448871
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 714; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
79 ASTRONOMY AND ASTROPHYSICS
CONVECTION
DOPPLER EFFECT
EIGENFUNCTIONS
ENERGY TRANSFER
FUNCTIONS
HEAT TRANSFER
MAIN SEQUENCE STARS
MASS TRANSFER
PERTURBATION THEORY
STARS
SUN