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arXiv · 1905.11827

Relations Between Molecular Cloud Structure Sizes and Line Widths in the Large Magellanic Cloud

Tony Wong·Annie Hughes·Kazuki Tokuda·Rémy Indebetouw·Toshikazu Onishi·Jeffrey B. Bandurski·C. -H. Rosie Chen·Yasuo Fukui·Simon C. O. Glover·Ralf S. Klessen·Jorge L. Pineda·Julia Roman-Duval·Marta Sewiło·Evan Wojciechowski·Sarolta Zahorecz
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Abstract

We present a comparative study of the size-line width relation for substructures within six molecular clouds in the Large Magellanic Cloud (LMC) mapped with the Atacama Large Millimeter/submillimeter Array (ALMA). Our sample extends our previous study, which compared a Planck detected cold cloud in the outskirts of the LMC with the 30 Doradus molecular cloud and found the typical line width for 1 pc radius structures to be 5 times larger in 30 Doradus. By observing clouds with intermediate levels of star formation activity, we find evidence that line width at a given size increases with increasing local and cloud-scale 8$μ$m intensity. At the same time, line width at a given size appears to independently correlate with measures of mass surface density. Our results suggest that both virial-like motions due to gravity and local energy injection by star formation feedback play important roles in determining intracloud dynamics.

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Tony Wong, Annie Hughes, Kazuki Tokuda, Rémy Indebetouw, Toshikazu Onishi, Jeffrey B. Bandurski, C. -H. Rosie Chen, Yasuo Fukui, Simon C. O. Glover, Ralf S. Klessen, Jorge L. Pineda, Julia Roman-Duval, Marta Sewiło, Evan Wojciechowski, Sarolta Zahorecz. 2019-09-15. Relations Between Molecular Cloud Structure Sizes and Line Widths in the Large Magellanic Cloud. https://doi.org/10.3847/1538-4357%2Fab46ba

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