Separatrix reconnection and periodic orbit annihilation in the Harper map.

Structure of the periodic accelerator orbits of the Harper map is investigated in detail from the viewpoint of underlying scenario of chaos in the area preserving nontwist map. Since the twist function of the Harper map is free from the polynomial local approximation, it admits rigorous treatment for the entire range of phase variable. The results obtained in the present analysis describes generic novel phenomena, which are outside of the applicability of the Kolmogorov-Arnol'd-Moser theory. (c) 1997 American Institute of Physics.