Simulations of emerging magnetic flux. I. The formation of stable coronal flux ropes

Leake, James E.; Linton, Mark G.; Török, Tibor

doi:10.1088/0004-637X/778/2/99

Title: Simulations of emerging magnetic flux. I. The formation of stable coronal flux ropes

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Abstract

We present results from three-dimensional visco-resistive magnetohydrodynamic simulations of the emergence of a convection zone magnetic flux tube into a solar atmosphere containing a pre-existing dipole coronal field, which is orientated to minimize reconnection with the emerging field. We observe that the emergence process is capable of producing a coronal flux rope by the transfer of twist from the convection zone, as found in previous simulations. We find that this flux rope is stable, with no evidence of a fast rise, and that its ultimate height in the corona is determined by the strength of the pre-existing dipole field. We also find that although the electric currents in the initial convection zone flux tube are almost perfectly neutralized, the resultant coronal flux rope carries a significant net current. These results suggest that flux tube emergence is capable of creating non-current-neutralized stable flux ropes in the corona, tethered by overlying potential fields, a magnetic configuration that is believed to be the source of coronal mass ejections.

Authors:

Leake, James E. ^[1]; Linton, Mark G. ^[2]; Török, Tibor ^[3]

College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States)
US Naval Research Laboratory 4555 Overlook Ave., SW Washington, DC 20375 (United States)
Predictive Science Inc., 9990 Mesa Rim Rd., Ste. 170, San Diego, CA 92121 (United States)

Publication Date:: Sun Dec 01 00:00:00 EST 2013

OSTI Identifier:: 22341971

Resource Type:: Journal Article

Journal Name:: Astrophysical Journal

Additional Journal Information:: Journal Volume: 778; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X

Country of Publication:: United States

Language:: English

Subject:: 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CONFIGURATION; CONVECTION; DIPOLES; ELECTRIC CURRENTS; MAGNETIC FIELDS; MAGNETIC FLUX; MAGNETOHYDRODYNAMICS; ROPES; SIMULATION; SOLAR ATMOSPHERE; SUN; THREE-DIMENSIONAL CALCULATIONS

Citation Formats


                    Leake, James E., Linton, Mark G., and Török, Tibor. Simulations of emerging magnetic flux. I. The formation of stable coronal flux ropes.  United States: N. p., 2013. 
        Web.  doi:10.1088/0004-637X/778/2/99.

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                    Leake, James E., Linton, Mark G., & Török, Tibor. Simulations of emerging magnetic flux. I. The formation of stable coronal flux ropes.  United States.  https://doi.org/10.1088/0004-637X/778/2/99

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                    Leake, James E., Linton, Mark G., and Török, Tibor. 2013.  
        "Simulations of emerging magnetic flux. I. The formation of stable coronal flux ropes".  United States.  https://doi.org/10.1088/0004-637X/778/2/99.

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@article{osti_22341971,

  title        = {Simulations of emerging magnetic flux. I. The formation of stable coronal flux ropes},

  author       = {Leake, James E. and Linton, Mark G. and Török, Tibor},

  abstractNote = {We present results from three-dimensional visco-resistive magnetohydrodynamic simulations of the emergence of a convection zone magnetic flux tube into a solar atmosphere containing a pre-existing dipole coronal field, which is orientated to minimize reconnection with the emerging field. We observe that the emergence process is capable of producing a coronal flux rope by the transfer of twist from the convection zone, as found in previous simulations. We find that this flux rope is stable, with no evidence of a fast rise, and that its ultimate height in the corona is determined by the strength of the pre-existing dipole field. We also find that although the electric currents in the initial convection zone flux tube are almost perfectly neutralized, the resultant coronal flux rope carries a significant net current. These results suggest that flux tube emergence is capable of creating non-current-neutralized stable flux ropes in the corona, tethered by overlying potential fields, a magnetic configuration that is believed to be the source of coronal mass ejections.},

  doi          = {10.1088/0004-637X/778/2/99},

  url          = {https://www.osti.gov/biblio/22341971},
  journal      = {Astrophysical Journal},

  issn         = {0004-637X},

  number       = 2,

  volume       = 778,

  place        = {United States},

  year         = {Sun Dec 01 00:00:00 EST 2013},

  month        = {Sun Dec 01 00:00:00 EST 2013}

}

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