Astronomy and Astrophysics – Astrophysics
Scientific paper
May 1980
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1980apj...238..175l&link_type=abstract
Astrophysical Journal, Part 1, vol. 238, May 15, 1980, p. 175-183.
Astronomy and Astrophysics
Astrophysics
33
Interstellar Magnetic Fields, Interstellar Matter, Magnetic Field Configurations, Magnetohydrodynamic Stability, Cosmic Rays, Lines Of Force, Milky Way Galaxy, Turbulence Effects
Scientific paper
An instability criterion is derived which applies to any horizontal equilibrium state of the interstellar gas and fields system, i.e., such that the magnetic field lines remain parallel to the galactic plane, and that all the physical quantities depend only on the height above the plane; an analytic calculation of the growth rate of the instability is also given. Results are applied to the four models proposed by Badhwar and Stephens to fit radio-continuum observations, and find that they are all unstable in a time short compared to the galactic age. Following Zweibel and Kulsrud, some of the effects due to a microturbulent component in the interstellar magnetic field are introduced into calculations and it is confirmed that they tend to lead toward an overall stabilization of the system; in this case, the most unstable modes are not those with a very short wavelength in the direction across the field lines and parallel to the plane. Still, as long as the adiabatic index of the gas is less than about 1.5, it is noted that all the static equilibrium configurations proposed to date to describe the interstellar medium are unstable, and that the system is more likely to be in a state of permanent agitation, fed in part by the type of instabilities studied throughout this series.
Asseo Estelle
Cesarsky Catherine J.
Lachièze-Rey Marc
Pellat Rene
No associations
LandOfFree
Energy principle and the interstellar medium. III - Plane-parallel configurations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Energy principle and the interstellar medium. III - Plane-parallel configurations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Energy principle and the interstellar medium. III - Plane-parallel configurations will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1359051