Estimates of the parallel diffusion coefficient in the 1°-wide squares chosen along the core of the Reticulum (magenta) and Eridu (green) filaments, for the fibre (top) and shell (bottom) geometries, for the same CR flux pervading the two clouds (filled symbols) and for the reduced CR flux in Eridu (open symbols). The data points and error bars respectively give the mean value in each ~5 pc-wide square and the rms dispersion at 0.5–0.7 pc scale inside each square. Different n_HI and κ_‖ scales are used for each geometry.