AN ANALYTIC SOLUTION TO THE STEADY-STATE DOUBLE ADIABATIC EQUATIONS

20 moment transport equations applicable to low beta-plasmas of thermal origin in rotating planetary magnetospheres are presented. An analytic solution is found for a set of simplified equations describing the steady-state transport of collisionless plasma neglecting heat flow effects, which is also known as the double adiabatic situation [Chew et al., 1956]. The new element of this analytic solution is a closed form solution for the variation of the parallel flow velocity, u parallel-to, along magnetic field lines. The solution is significantly different from the often used assumption that, in the collisionless regime, the divergence of the parallel flow velocity is negligible (cf. [Burgers, 1969]). It is shown that only T perpendicular-to/B remains constant along the field line (as predicted by earlier calculations), while the density, parallel temperature and parallel Mach number vary as n/B is-porportional-to 1/u parallel-to, T parallel-to is-proportional-to 1/u parallel-to 2, and M is-proportional-to u parallel-to 2, respectively (in contrast to earlier predictions of n/B = const, T parallel-to = const, and M parallel-to = const.).