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arXiv · 2507.01222

A catalog of molecular clouds possibly associated with Galactic infrared bubbles I. The Southern Galactic plane

Abstract

We have carried out a morphological search for molecular clouds possibly associated with 48 Galactic infrared bubbles with angular radii of $>1'$ in the southern Galactic plane of $295^\circ \le l\le 350^\circ$ and $|b|\le 1^\circ$ presented by Hanaoka et al. (2019). 116 molecular clouds in the $(l,b,V_{\rm LSR})$ space are identified from the archival $^{12}$CO~$J$~=~1--0 line data obtained by the Mopra Southern Galactic plane survey, where $V_{\rm LSR}$ is the CO-line radial velocity. The kinematic distances are derived from $V_{\rm LSR}$ using the most accurate rotation curve of the Milky Way. We also present measurements of velocity dispersion, size parameter, molecular mass, and virial mass of 116 molecular clouds. This catalog is presented to investigate star formation and the origin of molecular shells and cavities, possibly associated with infrared bubbles. CO line intensity maps and position-velocity diagrams of the molecular clouds are available online as supplementary data.

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Mikito Kohno, Yoshiaki Sofue, Yasuo Fukui, Kengo Tachihara. 2025-07-01. A catalog of molecular clouds possibly associated with Galactic infrared bubbles I. The Southern Galactic plane. https://arxiv.org/abs/2507.01222

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