Two-dimensional magnetohydrodynamic model of emerging magnetic flux in the solar atmosphere

Journal Article · Sun Oct 01 04:00:00 EDT 1989 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/167932· OSTI ID:5126020

Shibata, K; Tajima, T; Steinolfson, R S; Matsumoto, R ^[1]

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1. Texas Univ., Austin (USA) Chiba Univ. (Japan)

The nonlinear undular mode of the magnetic buoyancy instability in an isolated horizontal magnetic flux embedded in a two-temperature layered atmosphere (solar corona-chromosphere/photosphere) is investigated using a two-dimensional magnetohydrodynamic code. The results show that the flux sheet with beta of about 1 is initially located at the bottom of the photosphere, and that the gas slides down the expanding loop as the instability develops, with the evacuated loop rising as a result of enhanced magnetic buoyancy. The expansion of the magnetic loop in the nonlinear regime displays self-similar behavior. The rise velocity of the magnetic loop in the high chromosphere (10-15 km/s) and the velocity of downflow noted along the loop (30-50 km/s) are consistent with observed values for arch filament systems. 82 refs.

• OSTI ID: 5126020
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 345; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ATMOSPHERES
EXPANSION
FLUID MECHANICS
HYDRODYNAMICS
HYDROMAGNETIC WAVES
MAGNETIC FIELDS
MAGNETIC FLUX
MAGNETOHYDRODYNAMICS
MATHEMATICAL MODELS
MECHANICS
NONLINEAR PROBLEMS
SOLAR ACTIVITY
SOLAR ATMOSPHERE
SOLAR PROMINENCES
STABILITY
STAR MODELS
STARSPOTS
STELLAR ACTIVITY
SUNSPOTS
TWO-DIMENSIONAL CALCULATIONS