Two states for the $\hat{I}ž(1820)$ resonance

Abstract

We recall that the chiral unitary approach for the interaction of pseudoscalar mesons with the baryons of the decuplet predicts two states for the $\hat{I}ž(1820)$ resonance, one with a narrow width and the other one with a large width. We contrast this fact with the recent BESIII measurement of the $K^{-}\hat{I}›$ mass distribution in the $\ddot{I}ˆ(3686)$ decay to $K^{-}\hat{I}›\bar{\hat{I}}{ž}^{+}$, which demands a width much larger than the average of the PDG, and show how the consideration of the two $\hat{I}ž(1820)$ states provides a natural explanation to this apparent contradiction.

9 pages, 3 figures