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arXiv · 2002.12365

Neutral baryonic systems with strangeness

H. Garcilazo·A. Valcarce·J. Vijande
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Abstract

We review the status as regards the existence of three- and four-body bound states made of neutrons and $\Lambda$ hyperons. For interesting cases, the coupling to neutral baryonic systems made of charged particles of different strangeness has been addressed. There are strong arguments showing that the $\Lambda nn$ system has no bound states. $\Lambda\Lambda nn$ strong stable states are not favored by our current knowledge of the strangeness $-1$ and $-2$ baryon-baryon interactions. However, a possible $\Xi^- t$ quasibound state decaying to $\Lambda\Lambda nn$ might exist in nature. Similarly, there is a broad agreement about the nonexistence of $\Lambda\Lambda n$ bound states. However, the coupling to $\Xi NN$ states opens the door to a resonance above the $\Lambda\Lambda n$ threshold.

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H. Garcilazo, A. Valcarce, J. Vijande. 2020-02-27. Neutral baryonic systems with strangeness. https://doi.org/10.1142/s0218301319300091

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