Multi-$\bar{K}$ hypernuclei

Abstract

Relativistic mean field calculations of multi-$\bar{K}$ hypernuclei are performed by adding $K^-$ mesons to particle-stable configurations of nucleons, $Λ$ and $Ξ$ hyperons. For a given hypernuclear core, the calculated $\bar{K}$ separation energy $B_{\bar{K}}$ saturates with the number of $\bar{K}$ mesons for more than roughly 10 mesons, with $B_{\bar{K}}$ bounded from above by 200 MeV. The associated baryonic densities saturate at values 2-3 times nuclear-matter density within a small region where the $\bar{K}$-meson densities peak, similarly to what was found for multi-$\bar{K}$ nuclei. The calculations demonstrate that particle-stable multistrange $\{N,Λ,Ξ\}$ configurations are stable against strong-interaction conversions $Λ\to N \bar{K}$ and $Ξ\to N \bar{K} \bar{K}$, confirming and strengthening the conclusion that kaon condensation is unlikely to occur in strong-interaction self-bound strange hadronic matter.

21 pages, 7 figures, revised figures and text