1112.3409 (Thiem Hoang et al.)
Thiem Hoang, A. Lazarian
We consider the acceleration of very small dust grains including Polycyclic
Aromatic Hydrocarbons (PAHs) arising from the electrostatic interactions of
dust grains that have charge fluctuates in time due to charging events. We
simulate the charge fluctuations of very small grains due to their sticking
collisions with electrons and ions in plasma and the emission of photoelectrons
by UV photons using Monte Carlo method. We identify the acceleration induced by
the charge fluctuations as the dominant acceleration mechanism of very small
grains in the diffuse interstellar medium (ISM). We show that this acceleration
mechanism is more efficient for environments with low ionization, where the
charge fluctuations are slow but have a large amplitude. We also discuss the
implications of the present mechanism for grain coagulation and shattering in
the diffuse ISM, molecular clouds and protoplanetary disks.
View original:
http://arxiv.org/abs/1112.3409
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