LAUSR

In this paper, the smooth order-n positon solutions and b-positon solutions of the NLS-MB equation are constructed by the degenerate Darboux transformation (DT). The decomposition of the order-2, order-3, and order-4 positon solutions is discussed based on the decomposition of modulus square, and its approximate orbits and variable “phase shift” are also exhibited. Furthermore, we discuss the degeneration progress of the order-2 b-positon solution which means the central area of b-positon solution is a very good approximation of the rogue wave solution. The approximate trajectories of the order-2 b-positon solution are also discussed.