(2+1)-DIMENSIONAL DERIVATIVE NONLINEAR SCHRODINGER EQUATION

A(2+1)-dimensional multi-component derivative nonlinear Schr\ddotodinger (DNLS) equation is obtained from the symmetry constraint of the modified Kadomtsev-Petviashvili equation, The model is proved to be inte- grable under the meaning that it possesses the Paitdevé property and the infinitely many generalized symmetries which constitute a generalized W_\infty algebra, An integrable DNLS hierarchy is obtained from the flow equation of infinitely many symntetries of the DNLS equation.