Skip to main content Accessibility help
×
Home
Hostname: page-component-544b6db54f-n9d2k Total loading time: 0.18 Render date: 2021-10-18T10:08:19.709Z Has data issue: true Feature Flags: { "shouldUseShareProductTool": true, "shouldUseHypothesis": true, "isUnsiloEnabled": true, "metricsAbstractViews": false, "figures": true, "newCiteModal": false, "newCitedByModal": true, "newEcommerce": true, "newUsageEvents": true }

Signatures of turbulence in the dense interstellar medium

Published online by Cambridge University Press:  03 August 2017

E. Falgarone
Affiliation:
Radioastronomie Millimétrique, Ecole Normale Supérieure, 24 rue Lhomond, 75005 Paris, France
T.G. Phillips
Affiliation:
California Institute of Technology, 320-47, Pasadena CA 91125, USA

Abstract

HTML view is not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

We present an ensemble of recent observational results on molecular clouds which, taken separately, could all be understood by invoking various unrelated physical processes, but taken all together form a coherent ensemble stressing the imprints of turbulence in the physics of the cold interstellar medium. These results are first, the existence of wings in the molecular line profiles, which can be interpreted on statistical grounds as the signature of the intermittency of the velocity field in turbulent flows, second the fractal geometry of the cloud edges, with properties reminiscent of those of various surfaces studied in turbulent laboratory flows, and third, the fact that the dense gas fills only a very small fraction of the space. The last points are supported by CO multitransition observations of a few fields in nearby molecular clouds. They show that the excitation conditions are the same for the gas emitting in the linewings and in the linecores and are also remarkably uniform over a large range (factor 10) of column densities. An attractive interpretation of the molecular line data is that most of the 12CO(J=2—1) and (J=3—2) emissions arise in cold (Tk ≥ 10K) and dense (nH2 ∼ 104 cm —3 or more) structures distributed on a fractal set with no characteristic scale size greater than about 1000 AU.

Type
Velocity Field and Magnetic Field
Copyright
Copyright © Kluwer 1991 

References

Anselmet, F., Gagne, Y., and Hopfinger, E. J. 1984, J. Fluid Mech., 140, 63.CrossRefGoogle Scholar
Bazell, D. and Désert, F. X. 1988, Ap. J., 333, 353.CrossRefGoogle Scholar
Boissé, P. 1990, Astron. Astrophys., 228, 483.Google Scholar
Boreiko, R.T., Betz, A.L., and Zmuidzinas, J. 1990, Ap. J., 353, 181.CrossRefGoogle Scholar
Casoli, F., Dupraz, C., Combes, F., and Kazes, I. 1991 Astr. Ap. submitted.Google Scholar
Clemens, D.P., and Barvainis, R. 1988, Ap. J. Supp., 68, 257.CrossRefGoogle Scholar
Drdla, K., Knapp, G.R. and van Dishoeck, E.F. 1989, Ap. J., 345, 815.CrossRefGoogle Scholar
Elmegreen, B.G.: 1991, these proceedings.Google Scholar
Falgarone, E., and Pérault, M.: 1987, Physical Processes in Interstellar Clouds, eds. Morfill, G.E. and Scholer, M., Kluwer Acad. Publ. Google Scholar
Falgarone, E., and Pérault, M.: 1988, Astr. Ap., 205, L1.Google Scholar
Falgarone, E., and Phillips, T. G. 1990, Ap. J., 359, 344.CrossRefGoogle Scholar
Falgarone, E. 1991, From Ground-based to Space-borne Submillimeter Astronomy, eds. Longdon, N. and Kaldeich, B., ESA Publ. Google Scholar
Falgarone, E., Phillips, T. G., and Walker, C. 1991, submitted to Ap. J. Google Scholar
Falgarone, E., Puget, J.-L., and Pérault, M. 1991, in preparation.Google Scholar
Frerking, M.A., Keene, J.B., Blake, G.A., and Phillips, T.G. 1989, Ap. J., 344, 311.CrossRefGoogle Scholar
Frisch, U., Sulem, P. L., and Nelkin, M. 1978, J. Fluid Mech., 87, 719.CrossRefGoogle Scholar
Genzel, R., Harris, A.I., Jaffe, D.T. and Stutzki, J. 1988, Ap. J., 332, 1049.CrossRefGoogle Scholar
Heithausen, A., and Thaddeus, P. 1990, Ap. J. Letters, 353, L49.CrossRefGoogle Scholar
Jaffe, D.T., Genzel, R., Harris, A.I., Howe, J.E., Stacey, G.J., Stutzki, J. 1990, Ap. J., 353, 193.CrossRefGoogle Scholar
Keene, J., Blake, G.A., Phillips, T.G., Huggins, P.J., and Beichman, C.A. 1985, Ap. J., 299, 967.CrossRefGoogle Scholar
Keto, E.R., and Lattanzio, J.C. 1989, Ap. J., 346, 184.CrossRefGoogle Scholar
Kolmogorov, A.N. 1941: Dokl. Akad. Nauk. 26, 115.Google Scholar
Kolmogorov, A. N. 1962, J. Fluid Mech., 13, 82.CrossRefGoogle Scholar
Landau, L. D. and Lifchitz, E. M. 1959, Fluid Mechanics, Addison-Wesley.Google Scholar
Langer, W.D., and Penzias, A.A. 1990, Ap. J. in press.Google Scholar
Larson, R.B.: 1981, Monthly Notices Roy. Astron. Soc., 194, 809.CrossRefGoogle Scholar
Lee, Y., Snell, R.L. and Dickman, R.L. 1990, Ap. J., 355, 536.CrossRefGoogle Scholar
Lovejoy, S. 1982, Science, 216, 185.CrossRefGoogle Scholar
Magnani, L., Blitz, L., and Wendel, A. 1988, Ap. J. (Letters), 331, L127.Google Scholar
Magnani, L., Carpenter, J.M., Blitz, L., Kassim, N.E. and Nath, B.B. 1990, Ap. J. Suppl., 73, 747.CrossRefGoogle Scholar
Mandelbrot, B. B. 1982, The fractal geometry of nature, Freeman.Google Scholar
Mauersberger, R., Henkel, C., Wilson, T.L. and Harju, J. 1990, Astron. Astrophys., 223, 79.Google Scholar
Méneveau, 1989, PhD. dissertation, Yale University.Google Scholar
Mooney, T.J., and Solomon, P.M. 1990 in preparation.Google Scholar
Oboukhov, A.M. 1962, J. Fluid Mech., 13, 77.CrossRefGoogle Scholar
Penzias, A.A., Solomon, P.M., Jefferts, K.B., and Wilson, R.W. 1972, Ap. J. Letters, 174, L43.CrossRefGoogle Scholar
Pérault, M., Falgarone, E., and Puget, J.L. 1985, Astr. Ap., 152, 371.Google Scholar
Phillips, T.G., and Huggins, P.J. 1981, Ap. J., 251, 533.CrossRefGoogle Scholar
Sage, L.J., Shore, S.N. and Solomon, P.M. 1990, Ap. J., 351, 422.CrossRefGoogle Scholar
Scalo, J.: 1987, Interstellar Processes, eds. Hollenbach, D.J. and Thronson, H.A. Google Scholar
Scalo, J.M. 1990 Physical Processes in Fragmentation and Star Formation, eds Capuzzo-Dolcetta, R. et al., Kluwer Academic Publ.: Dordrecht.Google Scholar
Sreenivasan, K. R. and Méneveau, C. 1986, J. Fluid Mech., 173, 357.CrossRefGoogle Scholar
Stutzki, J., Stacey, G.J., Genzel, R., Harris, A.I., Jaffe, D.T., and Lugten, J.B. 1988, Ap. J., 332, 379.CrossRefGoogle Scholar
Ungerechts, H. and Thaddeus, P. 1987, Ap. J. Suppl, 63, 645.CrossRefGoogle Scholar
van Atta, C. W. and Park, J. 1971, Statistical Models and Turbulence, eds. Rosenblatt, M. and van Atta, C.: Springer.Google Scholar
Wakker, B.P., 1990, Ph.D. Dissertation, University of Leiden.Google Scholar
Zmuidzinas, J., Betz, A.L., Boreiko, R.T., Goldhaber, D.M. 1988, Ap. J., 335, 774.CrossRefGoogle Scholar
Zuckerman, B. and Evans, N.J. 1974, Ap. J., 192, L149.CrossRefGoogle Scholar
You have Access

Send article to Kindle

To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Signatures of turbulence in the dense interstellar medium
Available formats
×

Send article to Dropbox

To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

Signatures of turbulence in the dense interstellar medium
Available formats
×

Send article to Google Drive

To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

Signatures of turbulence in the dense interstellar medium
Available formats
×
×

Reply to: Submit a response

Please enter your response.

Your details

Please enter a valid email address.

Conflicting interests

Do you have any conflicting interests? *