Reduced D-Kaup–Newell soliton hierarchies from sl(2,ℝ) and so(3,ℝ)

Abstract

Two reduced D-Kaup–Newell spectral problems from sl(2,[Formula: see text]) and so(3,[Formula: see text]) are considered, and the corresponding soliton hierarchies are generated by using the zero curvature formulation. The resulting systems are shown to be bi-Hamiltonian and their hereditary recursion operators are explicitly computed.