The heating of a thermally conducting stratified medium. I. Self-gravitating gas threaded by magnetic fields

Journal Article · Tue Jul 01 00:00:00 EDT 1980 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/158117· OSTI ID:7091406

Lerche, I; Low, B C

Two theoretical problems are presented to illustrate the equilibrium structure of a gravitating gas threaded by magnetic fields. The gas is heated everywhere at a rate proportional to the local density and cooled by thermal conduction channeled along the magnetic field. The particular interest we pursue is the influence of anisotropic thermal conduction on the distribution of the gas. For this purpose, the magnetic field is taken to be force-free so that its presence is felt only through its effects of inducting anisotropy in the thermal conduction. In the first problem, the magnetic field has straight field lines that are nearly parallel. The simple field line geometry allows us to calculate, in closed form, the equilibria configurations of a gas slab which is cooled nonuniformly by thermal conduction along field lines which leave the gas slab at varying angles. A perturbation method is employed. The problem involves the gas having a free boundary, which is one of the unknowns to be determined. A discussion is given of the set of all possible equilibria so constructed. In the second problem there is no electric current flowing in the gas but there is a potential magnetic field having curved field lines. Exact solutions of equilibriums are presented to illustrate the heating of stellar and galactic coronas. These solutions show that the existence of a hot corona overlying a cool base arises naturally from heating in the presence of magnetic field lines, all originating and ending on the stellar or galactic surface.

• Research Organization: Department of Physics and The Enrico Fermi Institute, University of Chicago
• OSTI ID: 7091406
• Journal Information: Astrophys. J.; (United States), Vol. 239:1
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
MAGNETIC FIELDS
MAGNETIC FIELD CONFIGURATIONS
PLASMA
PLASMA HEATING
THERMAL CONDUCTION
BOUNDARY CONDITIONS
DISTURBANCES
EQUILIBRIUM
GASES
GRAVITATION
MAGNETOHYDRODYNAMICS
STELLAR ATMOSPHERES
ATMOSPHERES
ENERGY TRANSFER
FLUID MECHANICS
FLUIDS
HEAT TRANSFER
HEATING
HYDRODYNAMICS
MECHANICS
700101* - Fusion Energy- Plasma Research- Confinement
Heating
& Production