A Hydrodynamic Model of Alfvénic Wave Heating in a Coronal Loop and Its Chromospheric Footpoints

Jeffrey W. Reep, Alexander Russell, Lucas A. Tarr, James E. Leake

Research output: Contribution to journalArticle

8 Citations (Scopus)
116 Downloads (Pure)

Abstract

Alfvénic waves have been proposed as an important energy transport mechanism in coronal loops, capable of delivering energy to both the corona and chromosphere and giving rise to many observed features, of flaring and quiescent regions. In previous work, we established that resistive dissipation of waves (ambipolar diffusion) can drive strong chromospheric heating and evaporation, capable of producing flaring signatures. However, that model was based on a simplified assumption that the waves propagate instantly to the chromosphere, an assumption which the current work removes. Via a ray tracing method, we have implemented traveling waves in a field-aligned hydrodynamic simulation that dissipate locally as they propagate along the field line. We compare this method to and validate against the magnetohydrodynamics code Lare3D. We then examine the importance of travel times to the dynamics of the loop evolution, finding that (1) the ionization level of the plasma plays a critical role in determining the location and rate at which waves dissipate; (2) long duration waves effectively bore a hole into the chromosphere, allowing subsequent waves to penetrate deeper than previously expected, unlike an electron beam whose energy deposition rises in height as evaporation reduces the mean-free paths of the electrons; (3) the dissipation of these waves drives a pressure front that propagates to deeper depths, unlike energy deposition by an electron beam
Original languageEnglish
Article number101
Pages (from-to)1-13
Number of pages13
JournalAstrophysical Journal
Volume853
Issue number2
DOIs
Publication statusPublished - 26 Jan 2018

Fingerprint

coronal loops
hydrodynamics
heating
chromosphere
electron
dissipation
energy
evaporation
electron beams
ambipolar diffusion
ray tracing
traveling waves
mean free path
magnetohydrodynamics
coronas
travel
travel time
corona
signatures
ionization

Keywords

  • magnetohydrodynamics
  • Sun: atmosphere
  • Sun: corona
  • Sun: flares
  • waves

Cite this

Reep, Jeffrey W. ; Russell, Alexander ; Tarr, Lucas A. ; Leake, James E. / A Hydrodynamic Model of Alfvénic Wave Heating in a Coronal Loop and Its Chromospheric Footpoints. In: Astrophysical Journal. 2018 ; Vol. 853, No. 2. pp. 1-13.
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A Hydrodynamic Model of Alfvénic Wave Heating in a Coronal Loop and Its Chromospheric Footpoints. / Reep, Jeffrey W.; Russell, Alexander; Tarr, Lucas A.; Leake, James E.

In: Astrophysical Journal, Vol. 853, No. 2, 101, 26.01.2018, p. 1-13.

Research output: Contribution to journalArticle

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