The family of strange multiquarks as kaonic molecules bound by hard core attraction

I study the $Ds(2317)$ and $Ds(2457)$ discovered at BABAR, CLEO and BELLE, and find that they belong to a class of strange $S=-1$ multiquarks, which is equivalent to the class of kaonic molecules bound by hard core attraction. In this class of hadrons a kaon is trapped by a s-wave meson or baryon. To describe this class of multiquarks the Resonating Group Method is applied to a standard quark model with chiral symmetry breaking, and the hard core kaon-meson(baryon) interactions are extracted. A criterion is derived to classify the attractive channels. The mesons f0(980), Bs0+, Bs1+ and also the baryons with the quantum numbers of Lambda, Sigma_c, Sigma_b, Omega_cc, Omega_cb, Omega_bb belong to the new hadronic class of the Ds(2317) and Ds(2457)