Multi-lambda hypernuclei and the equation of state of hypermatter

Abstract

Within a relativistic mean-field theory (RMFT) experimental data on the single-particle spectra of lambda hypernuclei are well reproduced. It is shown that the coupling constants cannot be fixed unambiguously from the single-particle spectra. The stability and structure of multi-lambda hypernuclei is explored on the basis of the RMFT using the coupling constants as determined from the observed single lambda hypernuclear levels. It is predicted that multistrange nuclei exhibit an enhanced interaction radius, which further increases in the case of finite temperatures. We suggest that multi-lambda hypernuclei could be produced in high-energy heavy ions and observed in secondary noncharge-changing reactions. The equation of state of lambda matter and the possibility of pure lambda droplets are also discussed.

Attributes of a rotating neutron star with a hyperon core

“…There are different phenomenological prescriptions e.g., using the quark counting arguments based on SU(6) theory to fix the vector couplings, while, fixing the scalar couplings from the potential depths of hyperon in nuclear matter [10,35,47]. From various analysis the choice of the ratio of hyperon to nucleon coupling for σ meson x σ < 0.72 has been emphasized [9] and also from studies based on hypernuclear levels [48], the choice (x σ < 0.9) is bounded from above. Following this convention, in our present work we take x σ =g σH /g σN =0.7, x ω =g ωH /g ωN =0.783 and x ω =x ρ , to calculate the EOS for the neutron star matter.…”

Application of the density dependent hadron field theory to neutron star matter

“…RMF theory [12,13] allows to incorporate easily and consistently an enlarged set of hadronic degrees of freedom and has been succesfully applied to hypernuclei [14][15][16][17] and neutron stars [2,4,5]. Being a phenomenological model with its parameters usually adjusted to the properties of finite nuclei and their limited density range around ρ 0 , an extrapolation to higher densities has some uncertainties.…”

Quadrupole deformation(β,γ)of lightΛhypernuclei in a constrained relativistic mean field model: Shape evolution and shape polarization effect of theLü1, Zhao2, Zhou3 2011Phys. Rev. C

“…The self-consistent mean field models, either the nonrelativistic [26][27][28][29] or the relativistic ones [30][31][32][33][34][35][36][37][38][39][40][41][42], have been extensively used to reproduce the available hypernuclear data and/or make various predictions for hypernuclei. Up to now most of these studies focus on spherical systems.…”