Journal Article

The turbulent destruction of clouds – II. Mach number dependence, mass-loss rates and tail formation

J. M. Pittard, T. W. Hartquist and S. A. E. G. Falle

in Monthly Notices of the Royal Astronomical Society

Published on behalf of The Royal Astronomical Society

Volume 405, issue 2, pages 821-838
Published in print June 2010 | ISSN: 0035-8711
Published online June 2010 | e-ISSN: 1365-2966 | DOI: http://dx.doi.org/10.1111/j.1365-2966.2010.16504.x
The turbulent destruction of clouds – II. Mach number dependence, mass-loss rates and tail formation

More Like This

Show all results sharing this subject:

  • Astronomy and Astrophysics

GO

Show Summary Details

Preview

The turbulent destruction of a cloud subject to the passage of an adiabatic shock is studied. We find large discrepancies between the lifetime of the cloud and the analytical result of Hartquist et al. These differences appear to be due to the assumption in Hartquist et al. that mass loss occurs largely as a result of lower pressure regions on the surface of the cloud away from the stagnation point, whereas in reality Kelvin–Helmholtz (KH) instabilities play a dominant role in the cloud destruction. We find that the true lifetime of the cloud (defined as when all of the material from the core of the cloud is well mixed with the intercloud material in the hydrodynamic cells) is about 6 ×tKHD, where tKHD is the growth time-scale for the most disruptive, long-wavelength, KH instabilities. These findings have wide implications for diffuse sources where there is transfer of material between hot and cool phases.

The properties of the interaction as a function of the Mach number and cloud density contrast are also studied. The interaction is milder at lower Mach numbers with the most marked differences occurring at low shock Mach numbers when the post-shock gas is subsonic with respect to the cloud (i.e. M < 2.76). Material stripped off the cloud only forms a long ‘tail-like’ feature if .

Keywords: hydrodynamics; shock waves; turbulence; ISM: clouds; ISM: kinematics and dynamics; supernova remnants

Journal Article.  11153 words.  Illustrated.

Subjects: Astronomy and Astrophysics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.