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arXiv · 2012.09500

Distances to molecular clouds in the second Galactic quadrant

Qing-Zeng Yan·Ji Yang·Yan Sun·Yang Su·Ye Xu·Hongchi Wang·Xin Zhou·Chen Wang
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Abstract

We present distances to 76 medium-sized molecular clouds and an extra large-scale one in the second Galactic quadrant ($104.75^\circ <l<150.25^\circ $ and $|b|<5.25^\circ$), 73 of which are accurately measured for the first time. Molecular cloud samples are drawn from $l$-$b$-$V$ space ($-95 < V_{\rm LSR}< 25$ \kms) with the density-based spatial clustering of applications with noise (DBSCAN) algorithm, and distances are measured with the background-eliminated extinction-parallax (BEEP) method using extinctions and Gaia DR2 parallaxes. The range of measured distances to 76 molecular clouds is from 211 to 2631 pc, and the extra large-scale molecular cloud appears to be a coherent structure at about 1 kpc, across about 40\deg\ ($\sim$700 pc) in the Galactic longitude.

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Qing-Zeng Yan, Ji Yang, Yan Sun, Yang Su, Ye Xu, Hongchi Wang, Xin Zhou, Chen Wang. 2020-12-17. Distances to molecular clouds in the second Galactic quadrant. https://doi.org/10.1051/0004-6361/202039768

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