Review of phenomenological analyses of $\hat{I}{\cdot }^{(\prime )}\ddot{I}€$ resonances

Abstract

We present a robust analysis of the $\hat{I}{\cdot }^{(\prime )}\ddot{I}€$ system in COMPASS data. We fit the extracted relative phases and intensities with a coupled-channel formalism enforcing both unitarity and analyticity. We provide a robust extraction of a single exotic $\ddot{I}{€}_1(1600)$ decaying to both $\hat{I}{\cdot }^{(\prime )}\ddot{I}€$ final states, and the resonance parameters of the $a_2(1320)$ and $a_2^{\prime }(1700)$. We find no evidence for a second exotic state, which is compatible with recent Lattice QCD estimates.

Proceedings of the XIIIth Quark Confinement and the Hadron Spectrum conference, 31 July-6 August, 2018. Maynooth University, Ireland