2026-10-14T17:17:25Z https://www.scidb.cn/oai

10.57760/sciencedb.0121a 2026-09-10T14:06:19Z

2026-09-10 Extinction-based distances for 1751 $^{13}\text{CO}$ cloud structures in the Northern Galactic plane doi:10.57760/sciencedb.0121a en In the crowded velocity fields of the Galactic plane, line of sight blending introduces significant uncertainties, leading to varying degrees of contamination in the derived distances. Consequently, the effective disentanglement of molecular cloud members from unrelated dust components is critical to resolving this issue. These inversion techniques, combining cloud decomposition and jump point analysis, are essential for isolating individual cloud structures and eliminating distance contamination. Compared to $^{12}$CO, $^{13}$CO is generally optically thinner and traces column density more reliably. Although recent studies reveal significant internal substructure within $^{13}$CO clouds, the spectral profiles of these molecular clouds remain relatively simple, allowing them to be distinguished even in velocity-crowded regions and thus minimizing line of sight confusion. While previous efforts successfully applied similar techniques to limited regions (e.g., Cygnus), this work extends such studies to the entire northern Galactic plane. Specifically, we employ Gaussian decomposition and multi-jump point detection to accurately decompose cloud and extinction profiles, thereby mapping the 3D distribution and velocity field of molecular gas in the solar neighborhood across a wide range of spatial scales. This catalog aims to address the difficulty of kinematic distance determination along crowded sightlines in the inner Galactic plane, and provides a large and relatively homogeneous set of extinction-based distances. These distances are tied to velocity-decomposed MWISP $^{13}$CO ($J=1\text{--}0$) structures, and cover molecular clouds in the crowded inner-Galaxy regions.Ultimately, we performed distance measurements for approximately 3,600 cloud structures with angular areas larger than $\sim 43.25$ square arcminutes. Initial distance solutions were obtained for 1,969 of these clouds. Through manual inspection, combined with analyses of the linewidth-size relation, molecular gas scale heights, and the distance-velocity relation, we classified 218 clouds (Class III) as suffering from foreground. The 1,751 MCs with measured distances account for 53.42% of the total flux of the parent sample and 42.26% of the total flux of the full cloud catalog, i.e., the fraction of the cataloged $^{13}$CO flux contained in clouds with accepted distances. Solar Neighbour; molecular cloud; distance measure Shiyu Zhang Yang Su Xuepeng Chen Ji Yang Qing-Zeng Yan Juan Mei Min Fang Yan Sun Shaobo Zhang Miaomiao Zhang PUBLIC https://creativecommons.org/licenses/by-nc-nd/4.0/ dataset Science Data Bank