A possible interpretation of $\hat{I}›$ baryon spectrum with pentaquark components

Abstract

The $\hat{I}›$ baryon spectrum is studied within the SU(3) flavor symmetry in a constituent quark model. We found that it is rather difficult to accommodate some negative-parity $\hat{I}›$ resonances as single $q^{2}s$ ($q=u,d$ quarks) states in the conventional three-quark picture. The ground $q^{3}s\bar{q}$ pentaquark mass spectrum is evaluated and a possible interpretation is proposed in the work: the observed $\hat{I}›(1405)1/2^{-}$, $\hat{I}›(1670)1/2^{-}$ and $\hat{I}›(1800)1/2^{-}$ are three-state mixtures of two $p$-wave $q^{2}s$ states and one ground $q^{3}s\bar{q}$ pentaquark state, so are the $\hat{I}›(1520)3/2^{-}$, $\hat{I}›(1690)3/2^{-}$ and $\hat{I}›(2050)3/2^{-}$ resonances.

6 pages, 5 tables