PRS values (purple triangles), their errors and the significance threshold (short, horizontal bars) calculated for angles Δψ, between starlight polarisation and depolarisation canals in the western region. Additionally, the Δψ (orange circles) and the associated error are shown. The result for each bin is represented by a data point located at its lower border. The two panels represent two distinct sets of orientations of depolarisation canals, as noted in the top left corner of each panel. Lighter shaded area represents all bins in which we find alignment, while the darker shaded area marks the estimated minimum distance range.