Deformation of hypernuclei studied with antisymmetirzed molecular dynamics

An extended version of the antisymmetrized molecular dynamics to study structure of $p$-$sd$ shell hypernuclei is developed. By using an effective $\Lambda N$ interaction, we investigate energy curves of $^9_\Lambda$Be, $^{13}_\Lambda$C and $^{20,21}_\Lambda$Ne as function of nuclear quadrupole deformation. Change of nuclear deformation caused by $\Lambda$ particle is discussed. It is found that the $\Lambda$ in p-wave enhances nuclear deformation, while that in s-wave reduces it. This effect is most prominent in $^{13}_\Lambda$C. The possibility of the parity inversion in $^{20}_\Lambda$Ne is also examined.