Novel types of interactions between solitons in the (2+1)-dimensional asymmetric Nizhnik-Novikov-Veselov system

Using the extended tanh-function method (ETM) based on mapping method, the variable separation solutions of the (2+1)-dimensional asymmetric Nizhnik-Novikov-Veselov (ANNV) system are derived. By further studying, we find that these variable separation solutions, which seem independent, actually depend on each other. Based on the variable separation solution and by selecting appropriate functions, new types of interactions among semi-foldons and special dromions, peakons, foldons constructed by multi-valued functions are investigated. Moreover, The explicit phase shifts for all the local excitations offered by the quantity U have been given, and are applied to these novel interactions in detail. (C) 2006 Elsevier Ltd. All rights reserved.