Adiabatic accretion with e_rot = 0.3: mass “probability” distribution function (PDF) per bin of specific angular momentum along the rotation axis z (M_⊙ per kpc km s^-1), for the gas within r< 8 kpc. The color coding is the same as for the radial profiles (Fig. 3), covering 40 Myr. With no additional physics, the system overall preserves the initial angular momentum distribution (coherent counter-clockwise rotation).