Impurity effects in λ hypernuclei

The antisymmetrized molecular dynamics model is applied to investigate changes of the nuclear deformation caused by the addition of a Λ particle. We focus on the p-shell (_Λ¹³C), sd-shell (_Λ²¹Ne), and neutron-rich (_Λ¹²Be ) Λ hypernuclei. By performing a variation of calculation, it is found that the Λ particle reduces the nuclear deformation, which results from the competition between the energy of the core nucleus and the energy gain by adding the Λ particle. In _Λ²¹Ne and _Λ¹²Be, the difference of the Λ binding energy between structures is also studied. (author)