Grain Acceleration by Magnetohydrodynamic Turbulence: Gyroresonance Mechanism

  title={Grain Acceleration by Magnetohydrodynamic Turbulence: Gyroresonance Mechanism},
  author={Huirong Yan and Alexander Lazarian},
  journal={The Astrophysical Journal},
We discuss a new mechanism of dust acceleration that acts in a turbulent magnetized medium. The magnetohydrodynamic (MHD) turbulence includes both fluid motions and magnetic fluctuations. We show that while the fluid motions bring about grain motions through the drag, the electromagnetic fluctuations can accelerate grains through resonant interactions. In this Letter, we calculate the grain acceleration by the gyroresonance in the cold neutral medium. We consider both incompressible and… 

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