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arXiv · 2212.12283

$\Xi$-nuclear constraints from $\Xi^-$ emulsion capture events

Eliahu Friedman·Avraham Gal
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Abstract

All five KEK and J-PARC two-body $\Xi^-$+$^A$Z $\to$ $^{A'}_{\Lambda}$Z'+$^{A''}_{\Lambda}$Z'' capture events in light emulsion nuclei, including KISO and IBUKI in $^{14}$N, are consistent with Coulomb-assisted $1p_{\Xi^-}$ nuclear states. The underlying $\Xi$-nuclear potential is strongly attractive, with nuclear-matter depth $V_{\Xi}$ larger than 20 MeV. The recent $^{14}$N capture events KINKA and IRRAWADDY assigned by J-PARC E07 to $1s_{\Xi^-}$ nuclear states, and implying considerably shallower $V_{\Xi}$, have also another interpretation as $1p_{\Xi^0}$ nuclear states.

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Eliahu Friedman, Avraham Gal. 2022-12-23. $\Xi$-nuclear constraints from $\Xi^-$ emulsion capture events. https://doi.org/10.1051/epjconf/202227103002

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