Shape of Λ hypernuclei in the (β,γ) deformation plane

We study the shape of Λ hypernuclei in the full (β,γ) deformation plane, including both axially symmetric and triaxial quadrupole deformations. To this end, we use the constrained Skyrme Hartree-Fock+BCS method on a three-dimensional Cartesian mesh. The potential energy surface is analyzed for carbon hypernuclei as well as for sd-shell hypernuclei such as Λ27,29Si and Λ25,27Mg. We show that the potential energy surfaces in the (β,γ) plane of the hypernuclei and the corresponding core nuclei are similar to each other, although the addition of the Λ hyperon makes the energy surface somewhat softer along the γ direction.