천문학회지 (Journal of The Korean Astronomical Society)

  • 제40권4호
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  • Pages.119-122
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  • 2007
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  • 1225-4614(pISSN)
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  • 2288-890X(eISSN)
한국천문학회 (The Korean Astronomical Society)
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DENSITY AND VELOCITY PROFILES IN COLLAPSING CLOUD L694-2

  • Seo, Y.M. (Department of Physics and Astronomy, SeouI National University) ;
  • Hong, S.S. (Department of Physics and Astronomy, SeouI National University) ;
  • Lee, S.H. (Department of Physics and Astronomy, SeouI National University) ;
  • Park, Y.S. (Department of Physics and Astronomy, SeouI National University) ;
  • Kim, Jong-Soo (Korea Astronomy and Space Science Institute)
  • 발행 : 2007.12.31
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초록

From the HCN observations of dense molecular cloud L694-2, Lee et al.(2007) determined internal distributions of density and velocity for the cloud. The density profile collaborates roughly with the Bonnor- Ebert gas sphere, but the velocity field departs significantly from the result of numerical simulations that are started from the BE sphere. Taking L694-2 as an example of collapsing clouds, we have performed a series of collapse simulations and determined initial configurations for the cloud in such a way that the resulting density and velocity profiles both match with the empirically deduced ones. Among many trial configurations the cloud which is initially uniform in density and bound by an expanding envelop depicts most closely the empirically obtained profiles of both density and velocity.

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