Model DR at t = 300 yr and an inclination angle of i = 60°. Molecular mass–velocity relationship (black) for the 0 km s⁻¹ < v <100 km s⁻¹ radial velocity range and the best-fitting power law m(v) ∝ v^−γ (red). The best-fitting index value γ is shown inside each panel for two intervals: 0 km s⁻¹ < v < 10 km s⁻¹ (left) and 10km s⁻¹ < v < 100 km s⁻¹ (right). The j_mix parameter is also indicated (from top to bottom, j_mix = 0, 0.3, 0.6 and 1.0). The vertical axis displays the logarithm of the molecular mass (in g).