Dissipation in Compressible Mhd Turbulence

نویسندگان

  • James M. Stone
  • Eve C. Ostriker
  • Charles F. Gammie
چکیده

We report results of a three dimensional, high resolution (up to 512) numerical investigation of supersonic compressible magnetohydrodynamic turbulence. We consider both forced and decaying turbulence. The model parameters are appropriate to conditions found in Galactic molecular clouds. We find that the dissipation time of turbulence is of order the flow crossing time or smaller, even in the presence of strong magnetic fields. About half the dissipation occurs in shocks. Weak magnetic fields are amplified and tangled by the turbulence, while strong fields remain well ordered. Subject headings: MHD – turbulence – waves – ISM: kinematics and dynamics – ISM: magnetic fields

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تاریخ انتشار 2008