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

Abstract

A hypothesis of absolutely stable strange hadronic matter composed of $\Lambda (1405)$ baryons, here denoted ${\Lambda }^{\ast }$, is tested within many-body calculations performed using the Relativistic Mean-Field approach. In our calculations, we employed the ${\Lambda }^{\ast }{\Lambda }^{\ast }$ interaction compatible with the ${\Lambda }^{\ast }{\Lambda }^{\ast }$ binding energy $B_{{\Lambda }^{\ast }{\Lambda }^{\ast }}=40$~MeV given by the phenomenological energy-independent $\bar{K}N$ interaction model by Yamazaki and Akaishi (YA). We found that the binding energy per ${\Lambda }^{\ast }$, as well as the central density in ${\Lambda }^{\ast }$ many-body systems saturates for mass number $A\ge 120$, leaving ${\Lambda }^{\ast }$ 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.

Comments: Proceedings of the HYP2018 conference, Norfolk/Portsmouth, USA, June 24 - 29, 2018, submitted to AIP Conference Proceedings