Transport of charged dust grains into the galactic halo

TL;DR

This paper presents a 3D dynamical model showing how magnetic fields and supernova explosions drive charged dust grains from galactic disks into halos, with significant dust mass loss.

Contribution

It introduces a novel 3D model that incorporates magnetic fields, radiation, and collisions to simulate dust outflows from galactic disks.

Findings

Magnetic fields are crucial for accelerating dust grains.

Dust grains can reach heights up to 10 kpc in 10-20 Myr.

Dust mass loss rate can be as high as 0.03 solar masses per year.

Abstract

We develop a 3D dynamical model of dust outflows from galactic discs. The outflows are initiated by multiple SN explosions in a magnetized interstellar medium (ISM) with a gravitationally stratified density distribution. Dust grains are treated as particles in cells interacting collisionally with gas, and forced by stellar radiation of the disc and Lorenz force. We show that magnetic field plays a crucial role in accelerating the charged dust grains and expelling them out of the disc: in 10--20~Myr they can be elevated at distances up to 10~kpc above the galactic plane. The dust-to-gas ratio in the outflowing medium varies in the range $5 \cdot 10^{-4} - 5 \cdot 10^{-2}$ along the vertical stream. Overall the dust mass loss rate depends on the parameters of ISM and may reach up to $3\times 10^{-2}$~\Msun~yr$^{-1}$