No scale N=4 supergravity coupled to Yang-Mills: the scalar potential and super-Higgs effect

We derive the scalar potential of the effective theory of type 1113 orientifold with 3-form fluxes turned on in presence of nonAbelian brane coordinates. N = 4 supergravity predicts a positive semidefinite potential with vanishing cosmological constant in the vacuum of commuting coordinates, with a classical moduli space given by three radial moduli and three RR scalars which complete three copies of the coset (U(I, I + n)/ U(I) circle times U(I + n)), together with 6n D3-branes coordinates, n being the rank of the gauge group G. Implications for the super-Higgs mechanism are also discusse