Interplay of quark and meson degrees of freedom in a near-threshold resonance: multi-channel case

TL;DR

This paper explores the complex interactions between quark and meson components in near-threshold resonances across multiple channels, revealing rich phenomena like pole structures and amplitude zeros.

Contribution

It demonstrates the full complexity of near-threshold phenomena when both quark and meson dynamics produce weakly coupled poles in a multi-channel setting.

Findings

Identification of weakly coupled near-threshold poles

Analysis of t-matrix and production amplitude zeros

Effects of continuum channel interplay on resonance properties

Abstract

We investigate the interplay of quark and meson degrees of freedom in a physical state representing a near-threshold resonance for the case of multiple continuum channels. The aim is to demonstrate the full complexity of near-threshold phenomena. It turns out that those are especially rich, if both quark and meson dynamics generate simultaneously weakly coupled near-threshold poles in the S-matrix. We study the properties of this scenario in detail, such as t-matrix and production amplitude zeros, as well as various effects of the continuum channels interplay.