Accession Number : AD0674060

Title :   THE EQUILIBRIUM STRUCTURE OF A SHOCK-HEATED CORONA.

Descriptive Note : Doctoral thesis,

Corporate Author : HARVARD COLL OBSERVATORY CAMBRIDGE MASS

Personal Author(s) : Kopp,Roger A.

Report Date : JUN 1968

Pagination or Media Count : 308

Abstract : A theory of shock propagation in a spherical atmosphere is presented, which incorporates both the damping of a shock by its wake and changes of shock strength caused by non-uniform properties and hydrodynamic motions in the preshock gas. This theory is applied in conjunction with the time-averaged conservation equations for radial flow to determine the structure of a stellar corona whose quasi-steady dynamical state is maintained by a balance between shockwave dissipation, thermal conduction, radiation, and coronal expansion. For the sun's corona, it is shown that a single theoretical model is capable of simultaneously representing observations of coronal electron densities, properties of the solar wind in interplanetary space, and intensities of the solar ultraviolet emission lines. The gross energy balance of an expanding shock-heated corona is discussed, with particular reference to the numerical model which best represents the quietday sun. The processes of radiation, conduction, mechanical dissipation, and convective outflow are each examined as to their relative importance in determining the equilibrium structure of different atmospheric layers. (Author)

Descriptors :   (*SOLAR CORONA, MATHEMATICAL MODELS), SHOCK WAVES, HYDRODYNAMICS, THEORY, SOLAR WIND, SOLAR RADIATION, HEAT TRANSFER, THESES

Subject Categories : Astrophysics

Distribution Statement : APPROVED FOR PUBLIC RELEASE