TRAO KSP TIMES: Homogeneous, High-sensitivity, Multi-transition Spectral Maps toward the Orion A and Ophiuchus Cloud with a High-velocity Resolution.

  • 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) ;
  • Heyer, Mark H. (Department of Astronomy, University of Massachusetts) ;
  • 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) ;
  • Cho, Jungyeon (Department of Astronomy and Space Science, Chungnam National University) ;
  • Lee, Seokho (National Astronomical Observatory of Japan) ;
  • Tatematsu, Ken'ichi (National Astronomical Observatory of Japan) ;
  • Gaches, Brandt A.L. (Department of Astronomy, University of Massachusetts) ;
  • Yang, Yao-Lun (Department of Astronomy, University of Texas) ;
  • Chen, How-Huan (Department of Astronomy, University of Texas) ;
  • Lee, Youngung (Korea Astronomy and Space Science Institute) ;
  • Jung, Jae Hoon (Korea Astronomy and Space Science Institute) ;
  • Lee, Changhoon (Korea Astronomy and Space Science Institute)
  • Published : 2019.10.14

Abstract

Turbulence plays a crucial role in controlling star formation as it produces density fluctuation as well as non-thermal pressure against gravity. Therefore, turbulence controls the mode and tempo of star formation. However, despite a plenty of previous studies, 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 mapped the Orion A and the Ophiuchus clouds, in three sets of lines (13CO 1-0/C18O 1-0, HCN 1-0/HCO+ 1-0, and CS 2-1/N2H+ 1-0) with a high-velocity resolution (~0.1 km/s) using the TRAO 14-m telescope. The mean Trms for the observed maps are less than 0.25 K, and all these maps show uniform Trms values throughout the observed area. These homogeneous and high signal-to-noise ratio data provide the best chance to probe the nature of turbulence in two different star-forming clouds, the Orion A and Ophiuchus clouds. We present comparisons between the line intensities of different molecular tracers as well as the results of a Principal Component Analysis (PCA).

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