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arXiv · 2303.08170

Deviation from a Continuous and Universal Turbulence Cascade in NGC 6334 due to Massive Star Formation Activity

Junhao Liu·Qizhou Zhang·Hauyu Baobab Liu·Keping Qiu·Shanghuo Li·Zhi-Yun Li·Paul T. P. Ho·Josep Miquel Girart·Tao-Chung Ching·Huei-Ru Vivien Chen·Shih-Ping Lai·Ramprasad Rao·Ya-wen Tang
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Abstract

We use molecular line data from ALMA, SMA, JCMT, and NANTEN2 to study the multi-scale ($\sim$15-0.005 pc) velocity statistics in the massive star formation region NGC 6334. We find that the non-thermal motions revealed by the velocity dispersion function (VDF) stay supersonic over scales of several orders of magnitudes. The multi-scale non-thermal motions revealed by different instruments do not follow the same continuous power-law, which is because the massive star formation activities near central young stellar objects have increased the non-thermal motions in small-scale and high-density regions. The magnitudes of VDFs vary in different gas materials at the same scale, where the infrared dark clump N6334S in an early evolutionary stage shows a lower level of non-thermal motions than other more evolved clumps due to its more quiescent star formation activity. We find possible signs of small-scale-driven (e.g., by gravitational accretion or outflows) supersonic turbulence in clump N6334IV with a three-point VDF analysis. Our results clearly show that the scaling relation of velocity fields in NGC 6334 deviates from a continuous and universal turbulence cascade due to massive star formation activities.

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Junhao Liu, Qizhou Zhang, Hauyu Baobab Liu, Keping Qiu, Shanghuo Li, Zhi-Yun Li, Paul T. P. Ho, Josep Miquel Girart, Tao-Chung Ching, Huei-Ru Vivien Chen, Shih-Ping Lai, Ramprasad Rao, Ya-wen Tang. 2023-05-24. Deviation from a Continuous and Universal Turbulence Cascade in NGC 6334 due to Massive Star Formation Activity. https://doi.org/10.3847/1538-4357%2Facc4c0

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