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Building and maintaining a solar tachocline through convective dynamo action

Matilsky, Loren Isaac; Toomre, Juri

Editor(s)
Wolk, Scott

The dynamical maintenance of the Sun’s tachocline of rotational shear remains one of the outstanding mysteries of solar physics. We present a series of three-dimensional MHD anealastic simulations in rotating spherical shells that for the first time achieve a tachocline self-consistently, in which a dynamo operates within both the convection zone and underlying stable region. With the introduction of a small, random seed magnetic field to a hydrodynamic progenitor, the initially differentially rotating radiative interior is forced into solid-body rotation by a convectively excited dynamo, and afterward is maintained for centuries-long timescales. The overall result is similar in spirit to one of the “main contenders” for tachocline confinement—Gough and McIntyre (1998)—in which a primordial magnetic field stops the inward radiative spreading of the differential rotation. However, these new simulations using the Rayleigh code make no assumptions about the Sun’s fossil interior magnetic field. They thus offer a possibly more realistic magnetic confinement scenario for the tachocline that is here shown to be achieved by a fully nonlinear MHD convective dynamo operating in the solar interior.

Computational Resources for this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center. Rayleigh has been developed by Nicholas Featherstone with support by the NSF through the Computational Infrastructure for Geodynamics (CIG). This effort was supported by NSF grants NSF-0949446 and NSF-1550901. See the referenced publications by Featherstone et al., Hindman et al., and Matsui et al. for more details. This work is funded by NASA grant 80NSSC18K1127.
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  • Bice, Connor, & Toomre, Juri. (2018). Exploring the Role of a Tachocline in M-Dwarf Magnetism. Presented at the The 20th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun (CS20). http://doi.org/10.5281/zenodo.1410681

  • Bice, Connor & Toomre, Juri (2020). Probing the influence of a tachocline in simulated M-dwarf dynamos, The Astrophysical Journal, 893, 107

  • Featherstone, N. A., & Hindman, B. W. (2016). The Spectral Amplitude of Stellar Convection and Its Scaling in the High-Rayleigh-number Regime, ApJ, 818, 32

  • Nicholas Featherstone. (2018, April 28). geodynamics/Rayleigh: Bug-Fix-Release: 0.9.1 (Version v0.9.1). Zenodo. http://doi.org/10.5281/zenodo.1236565

  • Ferraro, V. C. A. (1937). The Non-uniform Rotation of the Sun and its Magnetic Field, Monthly Notices of the Royal Astronomical Society, 97, 458

  • Gough, Douglas O., & McIntyre, Michael E. (1998). Inevitability of a magnetic field in the Sun's radiative interior, Nature, 394, 755

  • Bradley W. Hindman et al (2020). Morphological Classification of the Convective Regimes in Rotating Stars, ApJ 898 120

  • Howe, Rachel, et al. (2000). Dynamic variations at the base of the solar convection zone, Science, 287, 2456

  • Matilsky, Loren I., Hindman, Bradley W., & Toomre, Juri. (2018). Exploring the Influence of Density Contrast on Solar Near-Surface Shear. Presented at the The 20th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun (CS20), Boston, MA: Zenodo. http://doi.org/10.5281/zenodo.1476707

  • Matilsky, Loren I., Hindman, Bradley W., & Toomre, Juri (2019). The role of downflows in establishing solar nearsurface shear, The Astrophysical Journal, 871, 217

  • Matilsky, Loren I. & Toomre, Juri (2020). Exploring bistability in the cycles of the solar dynamo through global simulations, The Astrophysical Journal, 892, 106

  • Matilsky, Loren I., Hindman, Bradley W., & Toomre, Juri (2020). Revisiting the Sun's strong differential rotation along radial lines", The Astrophysical Journal, 898, 111

  • Matsui, H., Heien, E., Aubert, J., Aurnou, J. M., Avery, M., et al. (2016). Performance benchmarks for a next generation numerical dynamo model, GGG, 17, 1586

  • Speigel, Edward A., & Zahn, Jean-Paul (1992). The solar tachocline, Astronomy & Astrophysics, 265, 106

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Publication date:
February 27, 2021
DOI:
10.5281/zenodo.4568544

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Keyword(s):
The Sun and the Heliosphere; Solar dynamo; solar rotation; solar convection; magnetohydrodynamics; helioseismology
Grants:
National Science Foundation:
  • Geoinformatics: Facility Support: Computational Infrastructure for Geodynamics (0949446)
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The 20.5th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun (CS20.5), virtually anywhere, March 2-4, 2021
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Version Made many errors in version 2 :-( 10.5281/zenodo.4568544 Feb 27, 2021
Version version 2 (version 1 didn't have the poster or acknowledgments) 10.5281/zenodo.4567661 Feb 27, 2021
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