Analysis of the structure of $Ξ(1690)$ through its decays

Abstract

The mass and pole residue of the first orbitally and radially excited $ Ξ$ state as well as the ground state residue are calculated by means of the two-point QCD sum rules. Using the obtained results for the spectroscopic parameters, the strong coupling constants relevant to the decays $Ξ(1690)\rightarrow ΣK$ and $Ξ(1690) \rightarrow ΛK$ are calculated within the light-cone QCD sum rules and width of these decay channels are estimated. The obtained results for the mass of $ \widetildeΞ $ and ratio of the $Br\Big(\widetildeΞ\rightarrow ΣK\Big)/Br\Big(\widetildeΞ\rightarrow ΛK\Big)$, with $ \widetildeΞ $ representing the orbitally excited state in $ Ξ$ channel, are in nice agreement with the experimental data of the Belle Collaboration. This allows us to conclude that the $Ξ(1690)$ state, most probably, has negative parity.

9 Pages, 5 Figures and 3 Tables. Some typos have been corrected and some new references have been added