Figure 1.

Examples of b(a) curves belonging to the class U0/TM. Examples of b(a) curves belonging to the class U0/TM, as described by Eq. (15). We have assumed for all the plots ω = 2, A₁ = 1 and Ψ₁ = 0. As predicted by Eq. (16), in the case M = 1 we obtain an ellipse with a ratio ω between the two semi-axes. Examples of the M = 2 case are shown in the plots (b), (c), (d) and (e), for different choices of the parameters A₂ and Ψ₂. As expected, three ellipses appear in the case U0/T3 (plot f).