Propagating Linear Waves in Convectively Unstable Stellar Models

A Perturbative Approach

E. Papini, Laurent Gizon, A. C. Birch

    Research output: Contribution to journalArticle

    Abstract

    Linear time-domain simulations of acoustic oscillations are unstable in the stellar convection zone. To overcome this problem it is customary to compute the oscillations of a stabilized background stellar model. The stabilization affects the result, however. Here we propose to use a perturbative approach (running the simulation twice) to approximately recover the acoustic wave field while preserving seismic reciprocity. To test the method we considered a 1D standard solar model. We found that the mode frequencies of the (unstable) standard solar model are well approximated by the perturbative approach within 1 μHz for low-degree modes with frequencies near 3 mHz. We also show that the perturbative approach is appropriate for correcting rotational-frequency kernels. Finally, we comment that the method can be generalized to wave propagation in 3D magnetized stellar interiors because the magnetic fields have stabilizing effects on convection.

    Original languageEnglish (US)
    Pages (from-to)1919-1929
    Number of pages11
    JournalSolar Physics
    Volume289
    Issue number6
    DOIs
    StatePublished - Jun 1 2014

    Fingerprint

    stellar models
    stellar convection
    convection
    oscillation
    stellar interiors
    oscillations
    reciprocity
    acoustics
    acoustic wave
    wave field
    preserving
    wave propagation
    simulation
    stabilization
    magnetic field
    magnetic fields
    method

    Keywords

    • Helioseismology
    • Magnetic fields
    • Numerical methods
    • Stellar models

    ASJC Scopus subject areas

    • Astronomy and Astrophysics
    • Space and Planetary Science

    Cite this

    Propagating Linear Waves in Convectively Unstable Stellar Models : A Perturbative Approach. / Papini, E.; Gizon, Laurent; Birch, A. C.

    In: Solar Physics, Vol. 289, No. 6, 01.06.2014, p. 1919-1929.

    Research output: Contribution to journalArticle

    Papini, E. ; Gizon, Laurent ; Birch, A. C. / Propagating Linear Waves in Convectively Unstable Stellar Models : A Perturbative Approach. In: Solar Physics. 2014 ; Vol. 289, No. 6. pp. 1919-1929.
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