Top: planet mass (M_J) vs. separation of the inferred planet (R_p, au) for three different values of the disk viscosity parameter α_visc. The top left panel shows all α_visc values overlaid together. The remaining panels show individual plots for α_visc = 10⁻², 10⁻³, and 10⁻⁴, respectively. The error bars represent uncertainties in the inferred planet mass and the measured gap radius. The plot highlights the dependence of inferred planet mass on α_visc, with lower viscosity requiring lower planet masses to carve equivalent gaps. Bottom: distribution of detected exo-planets plotted as mass (M_J) vs. separation (au). Blue points represent confirmed exoplanets from the exoplanet.eu database, where true masses are used when available and minimum masses (M × sin i) are used otherwise. Other coloured points correspond to the planet masses we inferred for different viscosities.