The resonant drag instability (RDI): acoustic modes

  title={The resonant drag instability (RDI): acoustic modes},
  author={Philip F. Hopkins and Jonathan Squire},
  journal={Monthly Notices of the Royal Astronomical Society},
  • P. Hopkins, J. Squire
  • Published 10 July 2017
  • Physics
  • Monthly Notices of the Royal Astronomical Society
Recently, Squire & Hopkins showed any coupled dust–gas mixture is subject to a class of linear ‘resonant drag instabilities’ (RDI). These can drive large dust-to-gas ratio fluctuations even at arbitrarily small dust-to-gas mass ratios μ. Here, we identify and study both resonant and new non-resonant instabilities, in the simple case where the gas satisfies neutral hydrodynamics and supports acoustic waves (ω^2=c^2_sk^2). The gas and dust are coupled via an arbitrary drag law and subject to… 

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