The $B^{(*)}\bar{K}^{(*)}$-coupled-channel system in the hidden-gauge approach

Abstract

In this work we provide predictions for bottom-strange molecular states within the Hidden Gauge Formalism. We study the coupled-channel scattering of $B^{(*)}\bar{K}^{(*)}$ states and, by fixing only one free parameter to obtain the mass of a new excited $B_s^0$ state seen by the LHCb, we predict the pole parameters of six states in this sector. Concretely, we get that the masses of the flavor partners of the $D_{s0}(2317)$ and $D_{s1}(2460)$ states in the bottom sector are $5760$ and $5802$ MeV for the $B\bar{K}$ ($J^P=0^+$) and $B^{*}\bar{K}$ ($1^+$) states, respectively. Moreover, the recently seen states by the LHCb with masses around $6100$ and $6160$ MeV can be interpreted as $B\bar{K}^*$ and $B^*\bar{K}^*$ molecular states, according to reasonable values of the pole parameters and the splitting between these two states obtained in our calculation.

Figures (2)

• Figure 1: Feynman diagrams for the interaction of the $B^{(\ast)} \bar{K}^{(\ast)}$ systems. The diagram on the right corresponds to the $B^\ast\bar{K}-B\bar{K}^\ast$ coupled-channel system via the exchange of $\pi$, $\eta$, and $\eta^\prime$.
• Figure 2: Feynman diagram for the loop interaction of the $B^{(\ast)} \bar{K}^\ast$ system with the self-energy of $K^\ast$.