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arXiv · 2309.14831

Comparison of $\bar{\hbox{N}}\hbox{N}$ optical models

Jaume Carbonell·Guillaume Hupin·Sławomir Wycech
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Abstract

We compare the strong part of the $\bar{\hbox{N}}\hbox{N}$ interaction obtained by the Nijmegen partial wave analysis and the results of some of the most popular $\bar{\hbox{N}}\hbox{N}$ optical potentials in configuration space. We have found severe discrepancies in most of the partial waves, especially above $p_{Lab}$=400 MeV/c where the partial wave analysis displays a resonant-like structure in the $^{31}$S$_0$ and $^{33}$P$_0$ waves. Some theoretical difficulties to interpret this behaviour in terms of dynamical resonances are pointed pout and an alternative explanation is suggested. A much better stability is observed in the low energy parameters, apart from some discrepancies due to the presence of near-threshold quasi-bound states in particular waves. Large deviations have also been found between the corresponding potentials, at short and medium-range ($r\gtrsim 1$ fm) distances.

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Jaume Carbonell, Guillaume Hupin, Sławomir Wycech. 2023-09-26. Comparison of $\bar{\hbox{N}}\hbox{N}$ optical models. https://arxiv.org/abs/2309.14831

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