The main result of [@felea-09a] was reported in relation with an intermittent route to chaos for the monopole vibrations close to the resonance phase of a nuclear interaction. Still, we mention that the purpose of these two coupled etudes was only to emphasize the detection of such intermission for the “nuclear billiards” and not to establish its type according to [@pomeau-80], nor to compare it with other intermittency patterns from known experimental results .

\[sec:1\]Toy model
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We continue the study on a classical dynamical system proposed by Burgio, Baldo *et al.* , system composed of a number of $A$ nucleons with no charge, spin, or internal structure. A two-dimensional deep Woods-Saxon potential well, regarded as “nuclear billiard”, is periodically hit by the nucleons. The Bohr Hamiltonian in polar coordinates is a sum of two components: kinetic ($E_{kin.}$) and potential ($E_{pot.}$), the kinetic one decoupling into radial ($E_r$), centrifugal ($E_L$), and collective terms ($E_{coll.}$):

$$E_{kin.} = E_r + E_L + E_{coll.} = {\sum_{j=1}^{A}}\left( \frac{p_{r_{j}}^{2}}{2m}+\frac{p_{\theta _{j}}^{2}}{2mr_{j}^{2}} \right)%
+\frac{p_{\alpha }^{2}}{2M},$$

$$E_{pot.} = {\sum_{j=1}^{A}} V\left(r_{j},R\left( \theta _{j}\right) \right)+\frac{M\Omega ^{2}\alpha ^{2}}{2}.$$

The phase space is defined by particle and collective momenta and their conjugate coordinates: $\left( r,p_{r}\right)$, $\left( \theta,p_{\theta}\right)$ and $\left( \alpha,p_{\alpha}\right)$. The collective 