Effects of isovector scalar δ–meson on Λ–hypernuclei

We analyze the effects of δ–meson on hypernuclei within the framework of relativistic mean field theory. The δ–meson is included into the Lagrangian for hypernuclei. The extra nucleon–meson coupling (g_δ) affects every piece of physical observables, like binding energy, radii and single-particle energies of hypernuclei. Magnitude of effects in hypernuclei is found to be relatively less than their normal nuclei because of the presence of Λ hyperon. Flipping of single-particle energy levels are observed with the strength of gδ in the considered hypernuclei as well as normal nuclei. The spin-orbit potentials are observed for considered hypernuclei and the effect of g_δ on spin-orbit potentials is also analyzed. The calculated Λ binding energy (B_Λ) are quite agreeable with experimental data. The sensitivity of B_Λ for s- and p- orbitals with the strength of g_δ is also analyzed. Lambda mean potential is investigated which is found to be consistent with other predictions. (author)