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arXiv · 1812.00630

Review of phenomenological analyses of $η^{(\prime)} π$ resonances

A. Rodas·A. Pilloni·A. Szczepaniak
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Abstract

We present a robust analysis of the $η^{(\prime)} π$ 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 $π_1(1600)$ decaying to both $η^{(\prime)} π$ final states, and the resonance parameters of the $a_2(1320)$ and $a'_2(1700)$. We find no evidence for a second exotic state, which is compatible with recent Lattice QCD estimates.

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A. Rodas, A. Pilloni, A. Szczepaniak. 2018-12-03. Review of phenomenological analyses of $η^{(\prime)} π$ resonances. https://arxiv.org/abs/1812.00630

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