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arXiv · 2003.08587

Local Molecular Gas toward the Aquila Rift Region

Yang Su·Ji Yang·Qing-zeng Yan·Yan Gong·Zhiwei Chen·Shaobo Zhang·Yan Sun·Miaomiao Zhang·Xuepeng Chen·Xin Zhou·Min Wang·Hongchi Wang·Ye Xu·Zhibo Jiang
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Abstract

We present the results of a ~250 square degrees CO mapping (+26d 4.1x10^5 Msun in the whole region. In fact, the mass of the molecular gas is dominated by the W40 giant molecular cloud (GMC) at ~474 pc (~1.4x10^5 Msun) and the GMC complex G036.0+01.0 at ~560-670 pc (~2.0x10^5 Msun), while the MCs at ~220-260pc have gas masses of 10^2-10^3 Msun. Interestingly, an ~80pc long filamentary MC G044.0-02.5 at a distance of ~404 pc shows a systematic velocity gradient along and perpendicular to the major axis of the filament. The HI gas with the enhanced emission has the similar spatial morphologies and velocity features compared to the corresponding CO structure, indicating that the large-scale converging HI flows are probably responsible for the formation of the MC. Meanwhile, the long filamentary MC consists of many sub-filaments with the lengths ranging from ~0.5 pc to several pc, as well as prevalent networks of filaments in other large-scale local MCs.

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Yang Su, Ji Yang, Qing-zeng Yan, Yan Gong, Zhiwei Chen, Shaobo Zhang, Yan Sun, Miaomiao Zhang, Xuepeng Chen, Xin Zhou, Min Wang, Hongchi Wang, Ye Xu, Zhibo Jiang. 2020-04-28. Local Molecular Gas toward the Aquila Rift Region. https://doi.org/10.3847/1538-4357%2Fab7fff

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