3D Magneto-hydrodynamic simulations of Parker instability with cosmic rays

Ying Yi Lo, Chung Ming Ko, Chih Yueh Wang

Research output: Contribution to journalArticlepeer-review

7 Scopus citations


This study investigates Parker instability in an interstellar medium (ISM) near the Galactic plane using three-dimensional magneto-hydrodynamic simulations. Parker instability arises from the presence of a magnetic field in a plasma, wherein the magnetic buoyant pressure expels the gas and cause the gas to move along the field lines. The process is thought to induce the formation of giant molecular clouds in the Galaxy. In this study, the effects of cosmic-ray (CR) diffusion are examined. The ISM at equilibrium is assumed to comprise a plasma fluid and a CR fluid at various temperatures, with a uniform magnetic field passing through it in the azimuthal direction of the Galactic disk. After a small perturbation, the unstable gas aggregates at the footpoint of the magnetic fields and forms dense blobs. The growth rate of the instability increases with the strength of the CR diffusion. The formation of dense clouds is enhanced by the effect of cosmic rays (CRs), whereas the shape of the clouds depends sensitively on the initial conditions of perturbation.

Original languageEnglish
Pages (from-to)177-179
Number of pages3
JournalComputer Physics Communications
Issue number1
StatePublished - Jan 2011


  • Cosmic rays
  • Instabilities
  • ISM: magnetic fields
  • MHD


Dive into the research topics of '3D Magneto-hydrodynamic simulations of Parker instability with cosmic rays'. Together they form a unique fingerprint.

Cite this