Visualisation of the parameter space of the different dynamical regimes for triple systems (Sect. 2.2). On the left a triple with m₁ = 1 M_⊙, m₂ = 0.5 M_⊙, m₃ = 0.75 M_⊙, and i = 0° is assumed. The black dotted lines represent constant Lidov-Kozai timescales of value 10⁴P_out, 10⁵P_out, 10⁶P_out, and 10⁷P_out. The higher-order (octupole) term of the three-body interaction is important below the green dash-dotted line assuming a limit at ϵ_oct = 0.005. The triple is in the semisecular regime below the blue dashed line – assuming the inner eccentricity is 0.99 or can be reached during the LK cycles. For lower values of e_in the line moves downwards. The system is not dynamically stable below the red solid line. Below the blue dashed and red solid line the secular approach breaks down. On the right, the shaded areas represent how the boundary of the corresponding colour moves for different stellar masses, assuming m₂, m₃ in [0.1, 0.9] M_⊙. For the red shaded area we also take into account how the boundary of dynamical stability shifts when the inclination varies between 0−180°.