Density (top) and migration map (bottom) of the Ṁ = 5 × 10^-8 M_⊙/yr disc with a lower penetration depth for cosmic rays. In the top plot, the black and white lines mark the transitions in the α viscosity parameter as defined by Eq. (12), the grey line marks the disc’s height H. In the bottom plot, the regions encircled in black enclose the regions of outward migration, while the vertical red line marks the ice line at 190 K.