Nitrogen (blue) and hydrogen (pink) fractionation profiles of HCN in the PDS 70 disk, assuming a radially constant ¹²C/¹³C = 69 value to convert the H¹³CN column density into an HCN column density. The ribbons indicate the 16th and 84th percentiles of the posterior distribution of the ratios. The dashed black line shows the integrated-intensity profile of the 855 μm continuum observations (Isella et al. 2019; Benisty et al. 2021). The hatched regions indicate the beam major axis of the data cubes of HCN isotopologs.