TRAO Key Science Program: mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES)

  • Yun, Hyeong-Sik (School of Space Research, Kyung Hee University) ;
  • Lee, Jeong-Eun (School of Space Research, Kyung Hee University) ;
  • Choi, Yunhee (School of Space Research, Kyung Hee University) ;
  • Lee, Seokho (School of Space Research, Kyung Hee University) ;
  • Baek, Giseon (School of Space Research, Kyung Hee University) ;
  • Lee, Yong-Hee (School of Space Research, Kyung Hee University) ;
  • Choi, Minho (Korea Astronomy and Space Science Institute) ;
  • Kang, Hyunwoo (Korea Astronomy and Space Science Institute) ;
  • Tatematsu, Ken'ichi (National Astronomical Observatory of Japan) ;
  • Gaches, Brandt A.L. (Department of Astronomy, University of Massachusetts) ;
  • Heyer, Mark H. (Department of Astronomy, University of Massachusetts) ;
  • Evans, Neal J. II (Korea Astronomy and Space Science Institute) ;
  • Offner, Stella S.R. (Department of Astronomy, University of Texas) ;
  • Yang, Yao-Lun (Department of Astronomy, University of Texas)
  • Published : 2018.05.08

Abstract

Turbulence is a phenomenon which largely determines the density and velocity fields in molecular clouds. Turbulence can produce density fluctuation which triggers a gravitational collapse, and it can also produce a non-thermal pressure against gravity. Therefore, turbulence controls the mode and tempo of star formation. However, despite many years of study, the properties of turbulence remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "apping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES; PI: Jeong-Eun Lee)", we have mapped two star-forming clouds, the Orion A and the ${\rho}$ Ophiuchus molecular clouds, in 3 sets of lines (13CO 1-0/C18O 1-0, HCN 1-0/HCO+ 1-0, and CS 2-1/N2H+ 1-0) using the TRAO 14-m telescope. We aim to map entire clouds with a high-velocity resolution (~0.05 km/s) to compare turbulent properties between two different star-forming environments. We will present the preliminary results using a statistical method, Principal Component Analysis (PCA), that is a useful tool to represent turbulent power spectrum.

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