EFFECTS OF SYMMETRY BREAKDOWN IN THE BIFURCATIONS OF PERIODIC-ORBITS OF A NONINTEGRABLE HAMILTONIAN SYSTEM

In this work we study numerically the breakdown of discrete symmetries in a Hamiltonian system with two degrees of freedom. The initial Hamiltonian is invariant under time-reversal (t --> -t) and reflexion through an axis (x --> -x). These symmetries are then broken by the insertion of a magnetic field and a term of the form gammax3. The effects of these perturbations are studied in terms of Poincare sections and periodic orbits. (C) 1994 Academic Press, Inc.