Null controllability of parabolic coupled system with control under constraints.

International audienceWe prove the null controllability of a parabolic system. The single control is common to both PDEs, distributed and subject to constraints. The studied model can be applied in dynamics of biological systems or in physics. First we study the problem associated to a similar linearized system. Then appropriate Carleman inequalities and a fixed-point argument are used to prove the null controllability results