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Dynamical conditions of dense clumps in dark clouds: a strategy for elucidation

Published online by Cambridge University Press:  03 August 2017

Sheo S. Prasad
Sheo S. Prasad*
Affiliation:
Lockheed Palo Alto Research Laboratory 3251 Hanover Street (MC: O/91-20; B255) Palo Alto, CA 94304; USA Departments of Physics and Astronomy University of Southern California Los Angeles, CA 90089-1341; USA

Abstract

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Chemical considerations and simplified dynamical modeling suggest that dark cloud cores may be incessantly evolving such that the time spent at high core densities decreases as the density increases. After reaching a high density, gravitationally contracting dark cloud cores may either form stars or expand to states of lower densities. Cloud mass and initial density are amongst the factors that may control the evolutionary fate of the core. This view is diametrically opposite of the common belief that dense cores may be in near mechanical equilibrium. Mutually consistent end-to-end modeling of the spectral line profiles and intensities is needed to discern the reality.

Type
Velocity Field and Magnetic Field
Information
Symposium - International Astronomical Union , Volume 147: Fragmentation of Molecular Clouds and Star Formation , 1991 , pp. 93 - 99
Copyright
Copyright © Kluwer 1991 

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