Espectroscopia Mes\'{o}nica Moderna: o Papel Fundamental da Unitariedade

Eef van Beveren; George Rupp

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arXiv · 2111.02565

Espectroscopia Mes\'{o}nica Moderna: o Papel Fundamental da Unitariedade

Eef van Beveren·George Rupp

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Abstract

The importance of implementing unitarity constraints in meson spectroscopy is very briefly outlined for Portuguese students of engineering sciences and therefore non-experts in the field. After explaining the profound differences between meson spectroscopy and atomic spectroscopy, attention is paid to the shortcomings of standard Breit-Wigner parametrisations in the case of broad and/or overlapping resonances. Finally, the manifestly unitary Resonance-Spectrum-Expansion model, which lies at the heart of a recent invited review paper by the present authors, is graphically presented, together with a simple yet typical application to the long-controversial $K_0^\star(700)$ resonance.

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Eef van Beveren, George Rupp. 2021-11-04. Espectroscopia Mes\'{o}nica Moderna: o Papel Fundamental da Unitariedade. https://arxiv.org/abs/2111.02565

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