Extinction-based distances for 1751 $^{13}\text{CO}$ cloud structures in the 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.