Meteor generated plasma columns in E-region ionosphere: fields and diffusion

Abstract

A meteoroid penetrating the Earth's atmosphere leaves behind a trail of dense plasma in the E-region ionosphere, a region where electrons are strongly magnetized while ions are demagnetized due to their frequent collisions with neutrals. While radar measurements of meteor trail evolution have been collected and used to infer meteor and atmospheric properties since the 1950s, no accurate quantitative model of trail fields and diffusion exists. This paper describes a theory and simulations of trail plasma physics which applies to the majority of small meteors. Unlike earlier papers, our theory assumes a significant angle between the geomagnetic field and the plasma trail and includes the important interaction between the trail and the background ionospheric plasma. This study provides quantitative knowledge of the spatial distribution and dynamics of the plasma density and electric field. This should enable meteor and atmospheric researchers to more accurately interpret radar observations of specular and non-specular meteor echoes.