Electric dipole moments and disalignment of interstellar dust grains
Abstract
The degree to which interstellar grains align with respect to the interstellar magnetic field depends on disaligning as well as aligning mechanisms. For decades, it was assumed that disalignment was due primarily to the random angular impulses a grain receives when colliding with gas-phase atoms. Recently, a new disalignment mechanism has been considered, which may be very potent for a grain that has a time-varying electric dipole moment and drifts across the magnetic field. We provide quantitative estimates of the disalignment times for silicate grains with size > approximately 0.1 micron. These appear to be shorter than the time-scale for alignment by radiative torques, unless the grains contain superparamagnetic inclusions.
Keywords
Cite
@article{arxiv.0905.2176,
title = {Electric dipole moments and disalignment of interstellar dust grains},
author = {Margaret E. Jordan and Joseph C. Weingartner},
journal= {arXiv preprint arXiv:0905.2176},
year = {2015}
}
Comments
12 pages, 9 figures, submitted to MNRAS