Density map of gas for the 16 simulations at the corresponding time for which τ = 2. The first three rows show a box of 10 kpc side while the last row shows a box of 20 kpc side. The model numbers are colour-encoded according to the corresponding stellar mass (from the lightest to the most massive from the top to the bottom, i.e. 9.5, 10, 10.5, and 11 in log₁₀(M_⊙)). The two left columns illustrate the model with a gas fraction of 10% while the two right columns illustrate the models with a gas fraction of 20%. The odd (even) reference number accounts for models without (with) a bulge.