Igor Ivonin

Invariant model for the plasma transition layer

The transition layer between different plasmas is investigated both analytically and numerically using the example of the penetration of the Solar wind plasma into the Earth’s magnetosphere. It is shown that quick and deep penetration is possible in the form of the squeezing of frozen-in fields without reconnection, which may create spatial structures (layers, current sheets) for plasmas having different frozen-in field invariants. The steady, unique distribution of plasmas in the transition layer is found to be determined by the plasma invariants only. A simple, four-fluid hydrodynamics model is applied both qualitatively and quantitatively to study the coexistence of the plasmas at the final stage of the penetration in the down cusp region. The typical features of satellite observations, such as the large variations of plasma density and temperature, as well as the large scale potential well of the electric field, are explained and reproduced in numerical simulations. The model predicts and explains the...