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arXiv · 2005.11564

The strangest non-strange meson is not so strange after all

Saša Ceci·Marin Vukšić·Branimir Zauner
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Abstract

The broad non-strange meson $f_0$(500) is considered to be a non-Breit-Wigner resonance. It is generally assumed that if a resonance is broad it can hardly be described by a Breit-Wigner form. We show here that is not true neither for the broad Z boson, nor for the much narrower $\Delta(1232)$, and explain why the $f_0$(500) fits with them perfectly. Key differences between them boil down to a single parameter: the angle at which we see the resonance pole from the threshold, which explains the background, the residue phase, and the difference between the pole and Breit-Wigner parameters.

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Saša Ceci, Marin Vukšić, Branimir Zauner. 2020-05-23. The strangest non-strange meson is not so strange after all. https://arxiv.org/abs/2005.11564

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