Antidecuplet candidate Ξ--(1862) as a heptaquark with the overlap of two antikaons and a nucleon

I study the very recently discovered S=-2 resonance Ξ--(1886) by the NA49 Collaboration at the CERN SPS. I find that repulsion excludes the Ξ-- as a ddssu s-wave pentaquark. I explore the Ξ-- as a heptaquark, equivalent to a N+K+K linear molecule, with positive parity and total isospin I=3/2. I find that the kaon-kaon repulsion is canceled by the attraction existing in the kaon-nucleon channels. In our framework this state is easier to bind than the Θ+ described by a π+K+N Borromean bound state. The remaining I=1/2 doublet and I=1 triplet of the exotic antidecuplet are also studied, and the coupling to p-wave decay channels is briefly addressed