Chaos analysis of a semi-classical nuclear billiard model Original Research Article

We consider several interacting nucleons moving in 2D and 3D Woods–Saxon type potential wells and hitting the vibrating surface. The Hamiltonian has a coupling term between the particle motion and the collective coordinate which generates a self consistent dynamics and take into account both, the spin and isospin degrees of freedom of the nucleons. The numerical simulation is based on the solutions of the Hamilton equations which was solved using an algorithm of Runge–Kutta type (order 4–5) having an optimized step size, taking into account that the absolute error for each variable is less than 10−6. Total energy is conserved with high accuracy, i.e. approx. 10−6 in absolute value. We analyze the chaotic behavior of the nonlinear dynamics system using Lyapunov exponents and Kolmogorov–Sinai entropy.