Well-posedness for multicomponent Schrodinger-gKdV systems and stability of solitary waves with prescribed mass

In this paper we prove the well-posedness issues of the associated initial value problem, the existence of nontrivial solutions with prescribed $L^2$-norm, and the stability of associated solitary waves for two classes of coupled nonlinear dispersive equations. The first problem here describes the nonlinear interaction between two Schr\"{o}dinger type short waves and a generalized Korteweg-de Vries type long wave and the second problem describes the nonlinear interaction of two generalized Korteweg-de Vries type long waves with a common Schr\"{o}dinger type short wave. The results here extend many of the previously obtained results for two-component coupled Schr\"{o}dinger-Korteweg-de Vries systems.