On the nature of the K*2(1430), K*3(1780), K*4(2045), K*5(2380) and K*6 as K*--multi-rho states

Abstract

We show that the $K_2^{\ast }(1430)$, $K_3^{\ast }(1780)$, $K_4^{\ast }(2045)$, $K_5^{\ast }(2380)$ and a not yet discovered $K_6^{\ast }$ resonance are basically molecules made of an increasing number of $\rho (770)$ and one $K^{\ast }(892)$ mesons. The idea relies on the fact that the vector-vector interaction in s-wave with spins aligned is very strong both for $\rho \rho$ and $K^{\ast }\rho$. We extend a recent work, where several resonances showed up as multi-$\rho (770)$ molecules, to the strange sector including the $K^{\ast }(892)$ into the system. The resonant structures show up in the multi-body scattering amplitudes, which are evaluated in terms of the unitary two-body vector-vector scattering amplitudes by using the fixed center approximation to the Faddeev equations.