Plasma Dynamics of Magnetic Flux Injection in the Solar Atmosphere

Abstract

view Abstract Citations (5) References (39) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Plasma Dynamics of Magnetic Flux Injection in the Solar Atmosphere Huba, J. D. ; Chen, J. Abstract A computational analysis of magnetic flux injection from the solar photo sphere into the solar chromosphere and corona is presented. The model is one-dimensional and describes the evolution of the plasma and neutrals in the vertical x-direction; the magnetic field is assumed to be unidirectional in the horizontal plane. The initial magnetic field profile is a step function (a magnetic piston): B = B0 + ΔB for x < x0 and B = B0 for x > x0. The field is then allowed to relax self-consistently for t >0 and x > xx0: a shock is launched followed by the relaxation of the magnetic piston. Simulation results are presented for different initial positions x0 of the field jump in the chromosphere. When the piston (ΔB ∼ tens of gauss) is very low in the chromosphere, a weak shock is launched that results in upward plasma and neutral velocities V ≃ few km s-1 in the upper chromosphere and corona; the plasma and neutrals only attain velocities V ≃ tens of m s-1- in the lower chromosphere. A quasi-steady state follows, and the piston does not relax significantly because the pressure change across the magnetic piston is small. When the piston is initiated in the upper chromosphere, a stronger shock is launched into the corona; plasma and neutral velocities V ≃ tens of km s-1 are generated. Subsequently, the magnetic field piston relaxes and penetrates the transition layer into the corona; the upward velocities are V ≃ hundreds of km s-1. At the same time, plasma and neutrals are being swept into the corona. Publication: The Astrophysical Journal Pub Date: September 1996 DOI: 10.1086/177791 Bibcode: 1996ApJ...469..412H Keywords: MAGNETOHYDRODYNAMICS: MHD; SUN: CORONA; SUN: CHROMOSPHERE; SUN: MAGNETIC FIELDS full text sources ADS |