Snowmass white paper: Need for amplitude analysis in the discovery of new hadrons

Abstract

We highlight the need for the development of comprehensive amplitude analysis methods to further our understanding of hadron spectroscopy. Reaction amplitudes constrained by first principles of S-matrix theory and by QCD phenomenology are needed to extract robust interpretations of the data from experiments and from lattice calculations.In the last two decades, high-energy physics experiments have delivered a lot of unexpected exotic hadron resonances, that challenge the minimal quark model lore of baryons with three quarks and mesons with a quark-antiquark pair. Candidates for tetraquarks, pentaquarks, molecules, and hadrons with gluonic degrees of freedom have been found [1,2]. Establishing the existence of isolated resonances that go beyond the minimal quark model is just the first step: one needs to identify the complete multiplets and study the differences and similarities among their members. This

Spectroscopic study of strangeness = –3 Ω– baryon*

“…The Nambu-Jona-Lasinio (NJL) approach has been used for calculating the mixing of three and five components in low-lying Ω states with negative parity [27]. The partial wave analysis of light baryons is also a very important tool for the spectroscopy of narrow experimental states [28][29][30][31]. The details of these models through comparison are described in Section III.…”