Correlation between the distribution of hydrogen volume density (n_H) derived from the Leike et al. (2020) 3D dust reconstruction and ¹²CO emission across distances and radial velocities as quantified by the projected Rayleigh statistic (V) using a 30.′0 FWHM derivative kernel. The three panels correspond to three different input data as follows. Left. 3D dust and ¹²CO at their native angular resolution, 6.′87 and 45", respectively. Center. 3D dust at its native angular resolution and ¹²CO smoothed to a 24.′6 FWHM resolution. Right. 3D dust and ¹²CO smoothed to a 24.′6 FWHM resolution. In all three cases, regions with S/N < 3 are excluded from the analysis.