Values of as a function of the mass ratio of colliding particles (μ) and the distance from Saturn ( a). Dashed lines (colored red) show the relation between μ and a for particles with ρ _p = 0.9 g cm ⁻³ for seven values of (0.4–1 with an increment of 0.1). Solid lines (colored blue) represent the case with ρ _p = 0.5 g cm ⁻³ for six values of (0.5–1). The locations of Saturn's rings are also shown.