Effects of a Λ hyperon on the negative-parity states of ^(20)Ne

The properties of the clusterized structure in ^(21)_(Λ)Ne are stud-ied in detail based on a beyond relativistic mean-field(RMF)model in a recent paper[1],“The interplay of single-particle and collective motions in the low-lying states of ^(21)_(Λ)Ne with quadrupole-octupole correlations”.The intrinsic mean-field states of ^(21)_(Λ)Ne with quadrupole and octupole constraints are projected on certain angular momenta and parities,and the generator coordinate method is used to simultaneously consider configurational mixing.

Impurity effects of theΛhyperon in the hypernuclear systems^(25)ΛMg and(29)ΛSi

Based on the beyond-mean-field Skyrme-Hartree-Fock model,impurity effects of theΛhyperon in the hypernuclear systems^(25)ΛMg and^(29)ΛSi are investigated,respectively.Four cases,in which theΛhyperon occupies the single-particle orbitals L[000]1+/2,L[110]1-/2,L[101]3-/2 and L[101]1-/2,are focused.In each case,the potential energy surface and the energy curves projected on certain angular momenta are employed to show the influence of theΛhyperon on the nuclear core.Beside the shrinkage effect that is induced by theΛhyperon occupying the sΛorbital,it is found that theΛhyperon on the pΛorbital,L[110]1-/2,drives the nuclear core toward a prolate shape,while the ones on the other two pΛorbitals,L[101]3-/2 and L[101]1-/2,drive the nuclear core toward an oblate shape.The energy spectra and the corresponding intra-band E2 transition rates for the rotational bands are given as a prediction for future experiments.

Beyond-mean-field study of^(37)_(Λ)Ar based on the Skyrme-Hartree-Fock model

We present the hypernuclear states of^(37)_ΛAr obtained using the Skyrme-Hartree-Fock(SHF)model and a beyond-mean-field approach,including angular momentum projection(AMP)and the generator coordinate method(GCM).A comprehensive energy spectrum is given,which includes normally deformed(ND)and super deformed(SD)hypernuclear states with positive or negative parities.Energy levels corresponding to the configurations in which aΛhyperon occupies the s-,p-,or sd-shell orbitals are discussed.For the s-shellΛ,we pay special attention to the ND and SD states corresponding to the configurations^(36)Ar^(N)\otimes s_Λand^(36)Ar^(S)otimes s_Λ,where^(36)Ar^(N)and^(36)Ar^(S)denote the ND and SD nuclear cores,respectively.The disagreements between different models over theΛseparation energy of the SD state in previous studies are revisited.For the p-shellΛ,four rotational bands are predicted,and the impurity effects are shown.Furthermore,two energy levels corresponding to the configurations^(36)Ar^otimesΛ[101](3)(2)^(-)and^(36)Ar^(S)otimesΛ[101](1)(2)^(-)are obtained below the separation threshold of^(36)Ar+Λwithin 0.5 MeV.For the sd-shellΛ,three bound states are found near the separation threshold,and the mechanism behind these states are discussed.

Effects of Λ hyperons on the deformations of even–even nuclei

The deformations of multi-Λ hypernuclei corresponding to even-even core nuclei ranging from^(8)Be to^(40)Ca with 2,4,6,and 8 hyperons are studied using the deformed Skyrme-Hartree-Fock approach.It is found that the deformations are reduced when adding 2 or 8 Λ hyperons,but enhanced when adding 4 or 6 Λ hyperons.These differences are attributed to the fact that Λ hyperons are filled gradually into the three deformed p orbits,of which the [110] 1/2^(-)orbit is prolately deformed and the degenerate [101]1/2^(-)and [101]3/2^(-)orbits are oblately deformed.