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arXiv · 2104.00421

Constraints on $Ξ^-$ nuclear interactions from capture events in emulsion

E. Friedman·A. Gal
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Abstract

Five $Ξ^- p\to ΛΛ$ two-body capture events in $^{12}$C and $^{14}$N emulsion nuclei, in which a pair of single-$Λ$ hypernuclei is formed and identified by their weak decay, have been observed in $(K^-,K^+)$ emulsion exposures at KEK and J-PARC. Applying a $Ξ^-$-nucleus optical potential methodology to study atomic and nuclear transitions, we confirm that these capture events occur from Coulomb assisted $1p_{Ξ^-}$ nuclear states. Long-range $ΞN$ shell-model correlations are found essential to achieve consistency between the $^{12}$C and $^{14}$N events. The resulting $Ξ$-nuclear interaction is strongly attractive, with $Ξ$ potential depth in nuclear matter $V_Ξ\gtrsim 20$ MeV. Implications to multi-strangeness features of dense matter are outlined.

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E. Friedman, A. Gal. 2021-08-06. Constraints on $Ξ^-$ nuclear interactions from capture events in emulsion. https://doi.org/10.1016/j.physletb.2021.136555

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