CO(1–0)-to-H₂ conversion factor prescription comparison Comparing the radial α_{¹²CO(1−0)} trend derived from binning the data (in color) and the trend derived from applying different prescriptions. The trend for M101 is shown in the left and for M51 on the right. Comparison of the derived trend when applying the α_{¹²CO(1−0)} prescription used Sun et al. (2022; dotted line), from Bolatto et al. (2013; dash-dotted line). The black horizontal line illustrates the average local solar neighborhood α_{¹²CO(1−0)} value. The green-shaded region is an approximate illustration of the central region of the galaxy, where conditions potentially change dramatically to the overall disk.