TIMES: mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale. I. the first result.

  • Yun, Hyeong-Sik (School of Space Research, Kyung Hee University) ;
  • Lee, Jeong-Eun (School of Space Research, Kyung Hee University) ;
  • Choi, Yunhee (Korea Astronomy and Space Science Institute) ;
  • Evans, Neal J. II (Korea Astronomy and Space Science Institute) ;
  • Offner, Stella S.R. (Department of Astronomy, University of Texas) ;
  • Lee, Yong-Hee (School of Space Research, Kyung Hee University) ;
  • Baek, Giseon (School of Space Research, Kyung Hee University) ;
  • Choi, Minho (Korea Astronomy and Space Science Institute) ;
  • Kang, Hyunwoo (Korea Astronomy and Space Science Institute) ;
  • Lee, Seokho (National Astronomical Observatory of Japan) ;
  • Tatematsu, Ken'ichi (National Astronomical Observatory of Japan) ;
  • Heyer, Mark H. (Department of Astronomy, University of Massachusetts) ;
  • Gaches, Brandt A.L. (Department of Astronomy, University of Massachusetts) ;
  • Yang, Yao-Lun (Department of Astronomy, University of Texas) ;
  • Jung, Jae Hoon (Korea Astronomy and Space Science Institute) ;
  • Lee, Changhoon (Korea Astronomy and Space Science Institute)
  • Published : 2019.04.10

Abstract

Turbulence is one of the natural phenomena in molecular clouds. It affects gas density and velocity fluctuation within the molecular clouds and 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), "mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES; PI: Jeong-Eun Lee)", we have fully mapped two star-forming molecular clouds, the Orion A and the Ophiuchus molecular clouds, in 3 sets of lines ($^{13}CO$ J=1-0, $C^{18}O$ J=1-0, HCN J=1-0, $HCO^+$ J=1-0, CS J=2-1, and $N_2H^+$ J=1-0) using the TRAO 14-m telescope. We apply a statistical analysis, Principal Component Analysis (PCA), which can recover an underlying turbulent-power spectrum from an observed P-P-V spectral map. We compare turbulence properties not only between the two clouds, but also between different parts within each cloud. We present the first result of our observation program.

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