Heating plasma loops in the solar corona

J. M. A. Ashbourn, L. C. Woods, R. Bingham

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

We find a new heat source term for hot coronal loops and include it in the energy equation. This term requires the loop to be hotter than the ambient corona and depends on the combined effect of electron fluid shear and the temperature gradient. Under certain circumstances, the shear drives the heat up the radial temperature gradient into a cross section of the magnetic flux tube from which it leaves by radiation and by conduction down the axial temperature gradient in the usual manner. The heat source is thus a surface term applied over the whole of the loop rather than a volume-distributed term, and its strength is proportional to the cube of the temperature. We apply it to the usual scaling law and obtain an expression for the radius of the flux tube for thermal equilibrium to hold. The temperature distribution around the plasma loop is determined and compared with recent observations and is found to be in satisfactory agreement with them.
LanguageEnglish
Pages941-948
Number of pages8
JournalAstrophysical Journal
Volume553
Issue number2
DOIs
Publication statusPublished - 1 Jun 2001

Fingerprint

plasma heating
solar corona
temperature gradient
corona
temperature gradients
heat source
heat sources
heating
plasma
tubes
shear
coronal loops
scaling laws
leaves
coronas
magnetic flux
temperature distribution
cross section
temperature
conduction

Keywords

  • MHD
  • plasmas
  • sun
  • corona

Cite this

Ashbourn, J. M. A. ; Woods, L. C. ; Bingham, R. / Heating plasma loops in the solar corona. In: Astrophysical Journal. 2001 ; Vol. 553, No. 2. pp. 941-948.
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Heating plasma loops in the solar corona. / Ashbourn, J. M. A.; Woods, L. C.; Bingham, R.

In: Astrophysical Journal, Vol. 553, No. 2, 01.06.2001, p. 941-948.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Heating plasma loops in the solar corona

AU - Ashbourn, J. M. A.

AU - Woods, L. C.

AU - Bingham, R.

N1 - (c) American Astronomical Society

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AB - We find a new heat source term for hot coronal loops and include it in the energy equation. This term requires the loop to be hotter than the ambient corona and depends on the combined effect of electron fluid shear and the temperature gradient. Under certain circumstances, the shear drives the heat up the radial temperature gradient into a cross section of the magnetic flux tube from which it leaves by radiation and by conduction down the axial temperature gradient in the usual manner. The heat source is thus a surface term applied over the whole of the loop rather than a volume-distributed term, and its strength is proportional to the cube of the temperature. We apply it to the usual scaling law and obtain an expression for the radius of the flux tube for thermal equilibrium to hold. The temperature distribution around the plasma loop is determined and compared with recent observations and is found to be in satisfactory agreement with them.

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