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arXiv · 2310.08180

A High-Mass Young Star-forming Core Escaping from Its Parental Filament

Zhiyuan Ren·Xi Chen·Tie Liu·Emma Mannfors·Leonardo Bronfman·Fengwei Xu·Siyi Feng·Hongli Liu·Fanyi Meng·Amelia. M. Stutz·Shanghuo Li·Chang Won Lee·Ke Wang·Jianwen Zhou·Di Li·Chen Wang·Chakali Eswaraiah·Anandmayee Tej·Long-Fei Chen·Hui Shi
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Abstract

We studied the unique kinematic properties in massive filament G352.63-1.07 at $10^3$-AU spatial scale with the dense molecular tracers observed with the Atacama Large Millimeter/submillimeter Array (ALMA). We find the central massive core M1 (12 $M_\odot$) being separated from the surrounding filament with a velocity difference of $v- {v}_{sys}=-2$ km/s and a transverse separation within 3 arcsec. Meanwhile, as shown in multiple dense-gas tracers, M1 has a spatial extension closely aligned with the main filament and is connected to the filament towards its both ends. M1 thus represents a very beginning state for a massive young star-forming core escaping from the parental filament, within a time scale of $\sim 4000$ years. Based on its kinetic energy ($3.5\times10^{44}$ erg), the core escape is unlikely solely due to the original filament motion or magnetic field, but requires more energetic events such as a rapid intense anisotropic collapse. The released energy also seems to noticeably increase the environmental turbulence. This may help the filament to become stabilized again.

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Zhiyuan Ren, Xi Chen, Tie Liu, Emma Mannfors, Leonardo Bronfman, Fengwei Xu, Siyi Feng, Hongli Liu, Fanyi Meng, Amelia. M. Stutz, Shanghuo Li, Chang Won Lee, Ke Wang, Jianwen Zhou, Di Li, Chen Wang, Chakali Eswaraiah, Anandmayee Tej, Long-Fei Chen, Hui Shi. 2023-10-12. A High-Mass Young Star-forming Core Escaping from Its Parental Filament. https://doi.org/10.3847/1538-4357/aced54

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