Open ion-exosphere with an asymmetric anisotropic velocity distribution

In: Bulletin de la Classe des Sciences de l'Académie Royale de Sciences, des Lettres et des Beaux-Arts de Belgique, Band 64, Heft 1, S. 539-561

Abstract

Expressions for the number density, the escape flux, the parallel and perpendicular momentum fluxes, and the energy flux in an open ion-exosphere, are set up under the following assumptions : (a) the velocity distribution function at the exobase is given by an asymmetric bimaxwellian depending on 4 parameters ; (b) along a magnetic field line the potential energy of a charged particle is a monotonie function and the magnetic field strength monotonically decreases to a constant value. A method which allows to calculate the 4 parameters of the velocity distribution for a given set of values of the state variables is outlined. Finally, the analytic formulae for the state variables are explicitely given for the special case that the velocity distribution at the exobase is a bimaxwellian.