Dissipation of kinetic energy in clumpy magnetic clouds

  • B. G. Elmegreen
Part II: Compared Internal Structure of Nearby Molecular Clouds
Part of the Lecture Notes in Physics book series (LNP, volume 237)


The dissipation of the kinetic energy of magnetically connected clumps in a molecular cloud is discussed. For low interclump densities, dissipation is by ion-neutral viscosity inside the clumps and in the interclump medium. Additional kinetic energy is lost by Alfvén wave propagation to the external medium. The internal dissipation is found to be slow enough that molecular clouds can remain cold in the presence of supersonic clump motions. Most dissipation is by wave propagation. In the absence of wave energy input from internal or external sources, the time scale for significant energy loss from a young giant molecular cloud is approximately 2 free fall times, and in a dense molecular cloud core it is approximately 15 free fall times.


Magnetic Field Line Molecular Cloud Energy Dissipation Rate Cloud Core Dissipation Time 
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  1. Clifford, P. and Elmegreen, B.G. 1983, M.N.R.A.S., 202, 629.Google Scholar
  2. Elmegreen, B.G. 1979, Astrophys.J., 232, 729.Google Scholar
  3. Elmegreen, B.G. 1985, Astrophys.J, submitted.Google Scholar
  4. Norman, C. and Silk, J. 1980, Astrophys.J., 238, 158.Google Scholar
  5. Oppenheimer, M. and Dalgarno, A. 1974, Astrophys.J., 192, 29.Google Scholar
  6. Spitzer, L. Jr. 1978, in Physical Processes in the Interstellar Medium, (New York: Interscience).Google Scholar
  7. Zuckerman, B. and Evans, N.J. 1974, Astrophys.J.(Lett.), 192, L149.Google Scholar
  8. Zweibel, E.G. and Josafatsson, K. 1983, Astrophys.J., 270, 511.Google Scholar

Copyright information

© Springer-Verlag 1985

Authors and Affiliations

  • B. G. Elmegreen
    • 1
  1. 1.IBM Thomas J. Watson Research CenterYorktown Heights

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