Elliptical dust growth in astrophysical plasmas

Dept. of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, Scotland, UK e-mail: craig@astro.gla.ac.uk

Received: 27 January 2006
Accepted: 27 June 2006

Abstract

Elongated dust grains exist in astrophysical plasmas. Anisotropic growth of elliptical dust grains, via plasma deposition, occurs if the deposited ions are non-inertial. In reality the extent of such growth depends upon the initial kinetic energy of the ions and the magnitude of the electric field in the sheath. Simulations of the dynamics of the ions in the sheath are reported, showing how elliptical growth is related to the initial eccentricity and size of the seed relative to the sheath length. Consequences for the eventual fate of elliptical dust are then discussed.