Further studies of nonmaxwellian effects associated with the thermal escape of a planetary atmosphere
Abstract
A recent calculation by Lindenfeld and Shizgal (1979) for the nonMaxwellian effects associated with the thermal escape of a dilute gas from a planetary atmosphere is extended. The modifications include retention of a nonlinear term in the integral equation for the velocity distribution function, neglected in the earlier work. The retention of the nonlinear term yields for low values of the escape parameter correction factors for the escape flux somewhat in better agreement with the MonteCarlo results. In addition, the escaping gas density in this paper is given by the barometric distribution, instead of the previous assumption of a constant dependence with altitude. A detailed discussion of the role of the altitude dependence of the number density on the escape flux is also presented.
 Publication:

Planetary and Space Science
 Pub Date:
 February 1980
 DOI:
 10.1016/00320633(80)900914
 Bibcode:
 1980P&SS...28..159S
 Keywords:

 Atmospheric Physics;
 Gas Dynamics;
 Planetary Atmospheres;
 Thermal Emission;
 Atmospheric Pressure;
 Earth (Planet);
 Escape Velocity;
 Gas Density;
 Helium;
 Hydrogen;
 Mars (Planet);
 MaxwellBoltzmann Density Function;
 Monte Carlo Method;
 Lunar and Planetary Exploration