Brueckner Rearrangement Effects in Λ5^5_\LambdaHe and ΛΛ6^6_{\Lambda\Lambda}He

Rearrangement effects in light hypernuclei are investigated in the framework of the Brueckner theory. We can estimate without detailed numerical calculations that the energy of the $\alpha$-core is reduced by more than 2.5 MeV when the $\Lambda$ adheres to $^4$He to form $^5_\Lambda$He. Similar assessment of rearrangement contributions is essential to deduce the strength of $\Lambda\Lambda$ interaction from experimentally observed $\Delta B_{\Lambda\Lambda}$. The recently observed experimental value of $\sim$ 1 MeV for the $\Delta B_{\Lambda\Lambda}$ of \hll suggests that the matrix element of $$ in \hll is around -2 MeV.Comment: 7 pages, to appear in Phys. Rev.

Structure of neutron-rich Λ\Lambda hypernuclei

Properties of light neutron-rich $\Lambda$ hypernuclei ($^{16}_{\Lambda}$C, $^{12}_{\Lambda}$Be, and $^{11}_{\Lambda}$Li) are calculated within the Skyrme-Hartree-Fock approach. Interplay between hypernuclear interaction features and properties of these hypernuclei is studied. Response of weakly bound neutron states to hyperon addition depends generally on core distortion by hyperon, and it is essentially different for the different states. This response is especially sensitive to details of the ${\Lambda}N$ interaction for $1p_{1/2}$ states. Implications of the nuclear spin-orbit potential and nuclear incompressibility in the neutron-rich system properties are inferred. Dependence of the $\Lambda$ binding energies in hypernuclei on $Z$ at fixed $A$ is discussed

Exotic hypernuclear systems and heavy ion collisions

We discuss perspectives in hypernuclear studies opened by their integration with heavy ion physics. Particularly, neutron–rich Λ hypernuclei and double–Λ hypernucleican be produced, which are hardly attainable by traditional reactions and can enrich our knowledge on hadronic interactions