Two-dimensional plot of the mass fraction at a given density and pressure for the w/h = 0.9 simulation at the end of the simulation (554 ky). Blue to black contours are increasing mass fraction contours (blue: 1E-6, green: 1E-5, yellow: 5E-5, orange: 1E-4, red: 5E-4, black: 2E-3). The dashed red line is the maximum density achieved in a plan-parallel 1D simulation : 4.8  × 10⁴ cm³. The total mass at a density above this limit is around 10 solar masses.