Exotic molecular meson states of B(*) K(*) nature

We evaluate theoretically the interaction of the open bottom and strange systems (B) over bar (K) over bar, (B) over bar * (K) over bar, (B) over bar (K) over bar * and (B) over bar* (K) over bar* to look for possible bound states which could correspond to exotic non-quark-antiquark mesons since they would contain at least one b and one s quarks. The s-wave scattering matrix is evaluated implementing unitarity by means of the Bethe-Salpeter equation, with the potential kernels obtained from contact and vector meson exchange mechanisms. The vertices needed are supplied from Lagrangians derived from suitable extensions of the hidden gauge symmetry approach to the bottom sector. We find poles below the respective thresholds for isospin 0 interaction and evaluate the widths of the different obtained states by including the main sources of imaginary part, which are the B *-> B gamma decay in the (B) over bar * (K) over bar channels, the K *-> K pi in the channels involving a K *, plus the box diagrams with (B) over bar (K) over bar and (B) over bar * (K) over bar intermediate states for the (B) over bar * (K) over bar * channels.

Automated summary

This study theoretically evaluates the interaction between open bottom and strange systems, aiming to find bound states that could correspond to exotic non-quark-antiquark mesons. The s-wave scattering matrix is calculated using the Bethe-Salpeter equation with potential kernels derived from contact and vector meson exchange mechanisms. Poles below the respective thresholds for isospin 0 interaction are found, and the widths of the obtained states are evaluated by considering various sources of imaginary parts.