Synthesized spectra of turbulent clouds

E. Falgarone, D. C. Lis, T. G. Phillips, A. Pouquet, D. H. Porter, P. R. Woodward

Research output: Contribution to journalArticle

92 Scopus citations

Abstract

A comparison has been made of the velocity structure of non-star-forming dense molecular clouds and the output of a 5123 hydrodynamic code for compressible gas displaying features of turbulence. A remarkable similarity exists between the interstellar line profiles and the velocity profiles found by integrating, with an optically thin assumption, through subsections of the simulation. This similarity is in terms of both the structure of individual spectra, showing skewness, multiple peaks, and wings, and also the variations of the spectra from point to point. It is possible to see the origin of the various velocity substructures and how they correlate with regions of high density and velocity divergence, or regions of high vorticity, by deprojecting individual spectra of the simulation. It is found that the interstellar medium spectra are best represented by the epoch of the simulation in which the energy spectrum is essentially Kolmogorov-like and initially developed shocks have been largely converted into vorticity structures. Further, it is found that the vorticity peaks ascribed to intermittency contribute to the non-Gaussian features and wings of the line profile, but at an intensity level that is weak compared to the contribution of the bulk of the flow.

Original languageEnglish (US)
Pages (from-to)728-740
Number of pages13
JournalAstrophysical Journal
Volume436
Issue number2
DOIs
StatePublished - Dec 1 1994

Keywords

  • Hydrodynamics
  • ISM: clouds
  • ISM: kinematics and dynamics
  • Turbulence

Fingerprint Dive into the research topics of 'Synthesized spectra of turbulent clouds'. Together they form a unique fingerprint.

  • Cite this

    Falgarone, E., Lis, D. C., Phillips, T. G., Pouquet, A., Porter, D. H., & Woodward, P. R. (1994). Synthesized spectra of turbulent clouds. Astrophysical Journal, 436(2), 728-740. https://doi.org/10.1086/174946