K-matrix analysis of theJP=3− and 2+dibaryon systems

A multichannel $K$-matrix formalism which accounts for the effect of inelastic thresholds is used to study the $J^P=3^{-} \mathrm{and} 2^{+}$ dibaryon systems. An analysis, carried out previously for the $J^P=2^{+}$ system, is presented for the $J^P=3^{-}$ system. The relationship between phase-shift behavior and background contributions to the scattering matrix is then probed by studying both $J^P$ systems using explicit $K$-matrix poles. Possible effects of the $\pi d$ channel are considered and a three-channel analysis is performed for the $J^P=2^{+}$ system. The analyses are consistent with the existence of a $J^P=3^{-}$ and $J^P=2^{+}$ dibaryon resonance.