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arXiv · 1904.01928

On the Stability of $\Lambda(1405)$ Matter

J. Hrtánková·N. Barnea·E. Friedman·A. Gal·J. Mareš·M. Schäfer
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Abstract

A hypothesis of absolutely stable strange hadronic matter composed of $\Lambda(1405)$ baryons, here denoted $\Lambda^*$, is tested within many-body calculations performed using the Relativistic Mean-Field approach. In our calculations, we employed the $\Lambda^*\Lambda^*$ interaction compatible with the $\Lambda^*\Lambda^*$ binding energy $B_{\Lambda^*\Lambda^*}=40$~MeV given by the phenomenological energy-independent $\bar{K}N$ interaction model by Yamazaki and Akaishi (YA). We found that the binding energy per $\Lambda^*$, as well as the central density in $\Lambda^*$ many-body systems saturates for mass number $A\geq120$, leaving $\Lambda^*$ aggregates highly unstable against strong interaction decay. Moreover, we confronted the YA interaction model with kaonic atom data and found that it fails to reproduce the $K^-$ single-nucleon absorption fractions at rest from bubble chamber experiments.

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J. Hrtánková, N. Barnea, E. Friedman, A. Gal, J. Mareš, M. Schäfer. 2019-04-03. On the Stability of $\Lambda(1405)$ Matter. https://doi.org/10.1063/1.5118413

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