A generalized Hirota–Satsuma coupled Korteweg–de Vries equation and Miura transformations

Abstract By introducing a 4×4 matrix spectral problem with three potentials, we propose a new hierarchy of nonlinear evolution equations. A typical equation in the hierarchy is a generalization of the Hirota–Satsuma coupled Korteweg–de Vries equation. Also, it is shown that the hierarchy possesses the generalized Hamiltonian form. Further, a Miura transformation related to the typical equation and its reductions are derived, from which some new coupled modified Korteweg–de Vries equations are obtained.