Epicyclic frequency, cold gas surface mass density, and the Toomre stability parameter as a function of galactocentric distance for disk- (blue) and bulge-dominated (red) galaxies, defined as having a bulge-to-total stellar mass ratio of B/T < 0.2 and B/T ≥ 0.9, respectively. Vertical lines show the annuli’s outer radii, as defined in Eq. (1). We add for comparison the value of the solar neighbourhood: We calculated κ_D,⊙ ≈ 0.046 Myr⁻¹, as derived from the Oort constants A = 15.6 km s⁻¹ kpc⁻¹ and B = −15.8 km s⁻¹ kpc⁻¹ taken from Guo & Qi (2023); Σ_g,⊙ ≈ 13 M_⊙ pc⁻² from Flynn et al. (2006); and Q_eff,⊙ ≈ 1.7 (Binney & Tremaine 2008, with Q_s,⊙ ≈ 2.7 and Q_g,⊙ ≈ 1.5), a typical value for disks (e.g. Rafikov 2001; Leroy et al. 2008; Feng et al. 2014; Westfall et al. 2014). Note that we did not calculate the Toomre stability parameter for annuli, where its surface density drops below 1 M_⊙ pc⁻² as we do not expect the formation of any star clusters at such low gaseous densities.