Level inversion in kaonic nuclei and the high-density nuclear equation of state

Abstract

It is very difficult for any nuclear model to pin down the saturation property and high-density equation of state (EOS) simultaneously because of high nonlinearity of the nuclear many-body problem. In this work, we propose, for the first time, to use the special property of light kaonic nuclei to characterize the relation between saturation property and high-density EOS. With a series of relativistic mean-field models, this special property is found to be the level inversion between orbitals 2S 1/2 and 1D 5/2 in light kaonic nuclei. This level inversion can serve as a theoretical laboratory to group the incompressibility at saturation density and the EOS at supra-normal densities simultaneously.

The drip lines of kaonic nuclei

“…levels of 27−32 K − Ne and their corresponding normal nuclei (a 0 = 0) obtained with different K − N interaction strengths a 0 (in units of MeV fm −3 ). by a RMF model [57] is not found in our SHF calculations.…”

“…A similar role of an additional K − in influencing s.p. levels was pointed out in the RMF approach [57]. In addition, an extension of the proton drip line is always found due to added kaon, in particular because of its negative electric charge.…”

Effects of a kaonic meson on the ground-state properties of nuclei *

“…The determination of the nuclear EOS with a certain accuracy is crucial for the understanding of the phenomena related to relativistic heavy-ion collisions and astrophysical objects, such as neutron stars, gravitational waves, etc. [55][56][57][58][59]. Moreover, the properties of exotic nuclei, such as their halo structure, have played a special role in constraining the nuclear forces, which are usually restrained to the neighborhood of the drip lines.…”

“…Moreover, the properties of exotic nuclei, such as their halo structure, have played a special role in constraining the nuclear forces, which are usually restrained to the neighborhood of the drip lines. The effects of kaons on the drip lines may provide a novel mechanism for the formation of exotic structure [57].…”

Strangeness production and hypernuclear formation in proton and antiproton induced reactions

“…In past several decades, strangeness nuclear physics has been extensively investigated both in experiments and in theories on the issues of hypernuclear physics, nuclear equation of state (EOS), hadronic matter properties, chiral symmetry restoration etc. Inclusion of the strangeness degree of freedom in a nucleus extends the research activities in nuclear physics, in particular the of hypernucleus and kaonic nucleus, hyperonnucleon and hyperon-hyperon interactions, probing the in-medium properties of hadrons [1][2][3][4][5][6][7]. Since the first observation of Λ-hypernuclide in nuclear multifragmentation reactions induced by cosmic rays in 1950s [8], a remarkable progress has been obtained in terrestrial laboratories for producing hypernuclides via different reaction mechanism, such as hadron (pion, K ± , proton, antiproton) induced reactions, bombarding the atomic nucleus with high-energy photons or electrons, and fragmentation reactions with high energy heavy-ion collisions.…”