----------------------------------------
Type of abstract: Invited for Student Workshop
Presenter Name: Lars Dyrud
Status of first author: student PhD
----------------------------------------
Title: 
Ionospheric plasma simulations of meteor trails
----------------------------------------
Authors: 
Lars Dyrud, ldyrud@bu.edu
Meers Oppenheim, Sigrid Close, Stephen Hunt, Axel vom Endt
----------------------------------------
Abstract: 
Meteor trails of ionization created from dust to sand size particles
are frequently observed by radars at altitudes from 80 - 120 km.
Meteor radars use the echoes from these trails to determine both
aeronomic and meteoric properties.  We use plasma simulations of
meteor trails to examine the factors effecting the interpretation
of radar signals from meteor trails.  These simulations demonstrate
that meteor trails develop a gradient drift type instability within
a fraction of a millisecond of formation.  Instability driven
turbulence and electrodynamics dominate the evolution of meteor
trails.  This result requires the reevaluation of certain assumptions
that allow for the interpretation of radar signals.  For example, we
find that meteor trails will not track neutral wind velocities
their initial stages of development, and diffusion in the plane
perpendicular to the magnetic field is turbulent and occurs at a
rate up to 10 times faster than expected from ambipolar diffusion.
We present a tutorial on E-region plasma conditions, instability
physics, the simulation of ionospheric plasmas, and conclude with
results and analysis of the simulations.
----------------------------------------
Upper Atmosphere and Ionosphere
Mesosphere
Analysis Techniques