baryon sector we are not using SU(4) symmetry. For the diagonal terms we also show that one is exchanging light vectors and the heavy quarks are spectators. In this case we obtain the same matrix elements as in Ref. [@angels], but there are differences in the non diagonal ones. Since in the dominant terms we are exchanging only light vectors and the heavy quarks are spectators, the interaction automatically respects heavy quark symmetry [@isgur; @neubert; @manohar]. The non diagonal terms which exchange heavy vectors do not fulfill heavy quark symmetry, but neither should them since these are terms of order $O(m_Q^{-2})$ in the heavy quark mass counting. In addition to the work of Ref. [@angels] we also include pseudoscalar-baryon(${3/2}^+$) components and we obtain two more states. We can identify two states of $J^{P}={1/2}^{-}$ and one of $J^{P}={3/2}^{-}$ with the states found in Ref. [@lhcbexp]. We also look for vector-baryon states and find three states at higher energies.

Formalism {#sec:form}
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Following Ref. [@romanets] we distinguish the cases with $J^{P}={1/2}^-$ and $J^{P}={3/2}^-$ and write the coupled channels. In Ref. [@romanets] 12 coupled channels are used ranging from thresholds $2965$ MeV to $3655$ MeV. The experimental states of Ref. [@lhcbexp] range from 