Λ*(1405)-matter: Stable or unstable?

A recent suggestion by Akaishi and Yamazaki (2017) [3] that purely-Lambda*(1405) nuclei provide the absolute minimum energy in charge-neutral baryon matter for baryon-number A greater than or similar to 8, is tested within RMF calculations. Abroad range of Lambda* interaction strengths, commensurate with ((K) over bar(K) over bar NN)(I=0) binding energy assumed to be of order 100 MeV, is scanned. It is found that the binding energy per Lambda*, B/A, saturates for A greater than or similar to 120 with values of B/A considerably below 100 MeV, implying that Lambda*(1405) matter is highly unstable against strong decay to Lambda and Sigma hyperon aggregates. The central density of Lambda* matter is found to saturate as well, at roughly twice nuclear matter density. Moreover, it is shown that the underlying very strong (K) over barN potentials, fitted for isospin I = 0 to the mass and width values of Lambda*(1405), fail to reproduce values of single-nucleon absorption fractions deduced across the periodic table from K- capture-at-rest bubble chamber experiments. (c) 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license.