Oral Presentation

Turbulent Properties in Star-Forming Molecular Clouds: Molecular Line Mapping with High-Velocity Resolution Using TRAO

Author(s): H.-S. Yun(KHU); J.-E. Lee(KHU); Y. Choi(KHU); S Lee(KHU); G. Baek(KHU); Y.-H. Lee(KHU); M. Choi(KASI); H. Kang(KASI); K. Tatematsu(NAOJ); B. A. L. Gaches(UMASS); M. H. Heyer(UMASS); N. J. Evans II(UT); S. S. R. Offner(UT); Y.-L. Yang(UT)

Presenter: Hyeong-Sik Yun (Kyung Hee University)

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), “Mapping turbulent properties of star-forming molecular clouds down to the sonic scale (PI: Jeong-Eun Lee)”, we have been mapping two star-forming clouds, the Orion A and the ρ 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 of a statistical analysis, Principal Component Analysis (PCA) which is a useful tool to represent turbulent power spectrum.