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Title: ON THE INTERNAL DYNAMICS OF THE STARLESS CORE L694-2

Abstract

In order to understand the internal dynamics of starless cores, we take L694-2 as an example of starless cores and investigate its internal dynamics by comparing observed data of L694-2 to our two hydrodynamical simulations, which involve the gravitational collapse of marginally unstable Bonnor-Ebert and uniform cores in a quiescent region. From the comparisons, we find that the density structures of the models agree well with the observed density distribution of L694-2, but the velocity fields and HCN line profiles of the models differ from the observed ones. From the differences in the velocity fields and the HCN line profiles, we have reached the following conclusions on the internal dynamics of L694-2. First, L694-2 has different internal dynamics from the gravitational collapse of the marginally unstable Bonnor-Ebert core. Second, L694-2 has an infall speed faster than any other core that undergoes the gravitational collapse with a Bonnor-Ebert-like density structure in a quiescent region. Third, L694-2 has almost no motion at its surface. From further simulations, in which cores are perturbed by supersonic shocks and affected by an expanding inter-core medium, the differences in the HCN line profiles could be reduced considerably.

Authors:
;  [1]; ; ;  [2];  [3]
  1. Korea Astronomy and Space Science Institute, Daejeon 305-348 (Korea, Republic of)
  2. Astronomy Program, Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of)
  3. Department of Earth Science Education, Korea National University of Education, Cheongwon 363-791 (Korea, Republic of)
Publication Date:
OSTI Identifier:
21578222
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 736; Journal Issue: 2; Other Information: DOI: 10.1088/0004-637X/736/2/153; Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DENSITY; GRAVITATIONAL COLLAPSE; HYDROCYANIC ACID; HYDRODYNAMICS; SIMULATION; STARS; VELOCITY; FLUID MECHANICS; HYDROGEN COMPOUNDS; INORGANIC ACIDS; INORGANIC COMPOUNDS; MECHANICS; PHYSICAL PROPERTIES

Citation Formats

Seo, Young Min, Lee, Chang Won, Hong, Seung Soo, Lee, Seok Ho, Park, Yong Sun, and Sohn, Jungjoo. ON THE INTERNAL DYNAMICS OF THE STARLESS CORE L694-2. United States: N. p., 2011. Web. doi:10.1088/0004-637X/736/2/153.
Seo, Young Min, Lee, Chang Won, Hong, Seung Soo, Lee, Seok Ho, Park, Yong Sun, & Sohn, Jungjoo. ON THE INTERNAL DYNAMICS OF THE STARLESS CORE L694-2. United States. doi:10.1088/0004-637X/736/2/153.
Seo, Young Min, Lee, Chang Won, Hong, Seung Soo, Lee, Seok Ho, Park, Yong Sun, and Sohn, Jungjoo. Mon . "ON THE INTERNAL DYNAMICS OF THE STARLESS CORE L694-2". United States. doi:10.1088/0004-637X/736/2/153.
@article{osti_21578222,
title = {ON THE INTERNAL DYNAMICS OF THE STARLESS CORE L694-2},
author = {Seo, Young Min and Lee, Chang Won and Hong, Seung Soo and Lee, Seok Ho and Park, Yong Sun and Sohn, Jungjoo},
abstractNote = {In order to understand the internal dynamics of starless cores, we take L694-2 as an example of starless cores and investigate its internal dynamics by comparing observed data of L694-2 to our two hydrodynamical simulations, which involve the gravitational collapse of marginally unstable Bonnor-Ebert and uniform cores in a quiescent region. From the comparisons, we find that the density structures of the models agree well with the observed density distribution of L694-2, but the velocity fields and HCN line profiles of the models differ from the observed ones. From the differences in the velocity fields and the HCN line profiles, we have reached the following conclusions on the internal dynamics of L694-2. First, L694-2 has different internal dynamics from the gravitational collapse of the marginally unstable Bonnor-Ebert core. Second, L694-2 has an infall speed faster than any other core that undergoes the gravitational collapse with a Bonnor-Ebert-like density structure in a quiescent region. Third, L694-2 has almost no motion at its surface. From further simulations, in which cores are perturbed by supersonic shocks and affected by an expanding inter-core medium, the differences in the HCN line profiles could be reduced considerably.},
doi = {10.1088/0004-637X/736/2/153},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 2,
volume = 736,
place = {United States},
year = {2011},
month = {8}
}