1School of Mathematics and Physics, North China Electric Power University, Beijing 102206 2School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191
Abstract：The isoscalar giant monopole resonances (ISGMRs) of hypernuclei $^{42}_{{\Lambda}{\Lambda}}$Ca, $^{122}_{{\Lambda}{\Lambda}}$Sn, and $^{210}_{{\Lambda}{\Lambda}}$Pb are investigated using a fully self-consistent Skyrme–Hartree–Fock plus random phase approximation method. The Skyrme-type forces, SGII, No.5 and S${\Lambda}{\Lambda}$1, are adopted to describe the nucleon–nucleon, ${\Lambda}$ hyperon–nucleon and ${\Lambda}$ hyperon–${\Lambda}$ hyperon (${\Lambda} {\Lambda}$) interactions, respectively. For a given hyperon fraction, we find that effects of ${\Lambda} {\Lambda}$ interaction on the properties of infinite symmetric nuclear matter and finite hypernuclei are very small. The ISGMR strengths are shifted to the high energy region when two ${\Lambda}$ are added into normal nuclei. The changes are from two parts, one is due to the mean field calculations, and the other is from the residual interaction associated with ${\Lambda}$ hyperons. The constrained energies are increased by about 0.5–0.7 MeV, which consequently enhances the effective incompressibility modulus of hypernuclei.
2018, Vol. 35 
