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arXiv · 2309.08998

Understanding the Kinetic Energy deposition within Molecular Clouds

Lixia Yuan·Ji Yang·Fujun Du·Yang Su·Shaobo Zhang·Qing-Zeng Yan·Yan Sun·Xin Zhou·Xuepeng Chen·Hongchi Wang·Zhiwei Chen
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Abstract

According to the structures traced by $^{13}$CO spectral lines within the $^{12}$CO molecular clouds (MCs), we investigate the contributions of their internal gas motions and relative motions to the total velocity dispersions of $^{12}$CO MCs. Our samples of 2851 $^{12}$CO MCs harbor a total of 9556 individual $^{13}$CO structures, among which 1848 MCs ($\sim$ 65$\%$) have one individual $^{13}$CO structure and the other 1003 MCs ($\sim$ 35$\%$) have multiple $^{13}$CO structures. We find that the contribution of the relative motion between $^{13}$CO structures ($σ_{\rm ^{13}CO, re}$) is larger than that from their internal gas motion ($σ_{\rm ^{13}CO, in}$) in $\sim$ 62$\%$ of 1003 MCs in the `multiple' regime. In addition, we find the $σ_{\rm ^{13}CO, re}$ tends to increase with the total velocity dispersion($σ_{\rm ^{12}CO, tot}$) in our samples, especially for the MCs having multiple $^{13}$CO structures. This result provides a manifestation of the macro-turbulent within MCs, which gradually becomes the dominant way to store the kinetic energy along with the development of MC scales.

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Lixia Yuan, Ji Yang, Fujun Du, Yang Su, Shaobo Zhang, Qing-Zeng Yan, Yan Sun, Xin Zhou, Xuepeng Chen, Hongchi Wang, Zhiwei Chen. 2023-09-16. Understanding the Kinetic Energy deposition within Molecular Clouds. https://arxiv.org/abs/2309.08998

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