Helioseismology of sunspots

Confronting observations with three-dimensional MHD simulations of wave propagation

R. Cameron, Laurent Gizon, T. L. Duvall

    Research output: Contribution to journalArticle

    Abstract

    The propagation of solar waves through the sunspot of AR9787 is observed by using temporal cross-correlations of SOHO/MDI Dopplergrams. We then use three-dimensional MHD numerical simulations to compute the propagation of wave packets through self-similar magnetohydrostatic sunspot models. The simulations are set up in such a way as to allow a comparison with observed cross-covariances (except in the immediate vicinity of the sunspot). We find that the simulation and the f-mode observations are in good agreement when the model sunspot has a peak field strength of 3 kG at the photosphere and less so for lower field strengths. Constraining the sunspot model with helioseismology is only possible because the direct effect of the magnetic field on the waves has been fully taken into account. Our work shows that the full-waveform modeling of sunspots is feasible.

    Original languageEnglish (US)
    Pages (from-to)291-308
    Number of pages18
    JournalSolar Physics
    Volume251
    Issue number1-2
    DOIs
    StatePublished - Sep 1 2008

    Fingerprint

    helioseismology
    sunspots
    sunspot
    wave propagation
    simulation
    field strength
    magnetohydrostatics
    propagation
    photosphere
    wave packets
    cross correlation
    waveforms
    magnetic field
    magnetic fields
    modeling

    Keywords

    • Sun: helioseismology
    • Sun: magnetic fields
    • Sun: sunspots

    ASJC Scopus subject areas

    • Astronomy and Astrophysics
    • Space and Planetary Science

    Cite this

    Helioseismology of sunspots : Confronting observations with three-dimensional MHD simulations of wave propagation. / Cameron, R.; Gizon, Laurent; Duvall, T. L.

    In: Solar Physics, Vol. 251, No. 1-2, 01.09.2008, p. 291-308.

    Research output: Contribution to journalArticle

    Cameron, R. ; Gizon, Laurent ; Duvall, T. L. / Helioseismology of sunspots : Confronting observations with three-dimensional MHD simulations of wave propagation. In: Solar Physics. 2008 ; Vol. 251, No. 1-2. pp. 291-308.
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