An extended version of antisymmetrized molecular dynamics was developed to study the structure of p-sd shell hypernuclei. By using an effective N interaction, we investigated the energy curves of 9 Be, 13 C, and 20,21 Ne as a function of nuclear quadrupole deformation. The changes to nuclear deformation caused by particles are discussed. We found that in the p wave enhances nuclear deformation, while that in the s wave reduces it. This effect is most prominent in 13 C. The possibility of parity inversion in 20 Ne is also examined.

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The response to the addition of a hyperon is investigated for the deformed states such as superdeformation in 41

The stiff equation of state (EoS) giving the neutron-star mass of 2M⊙ suggests the existence of strongly repulsive many-body effect (MBE) not only in nucleon channels but also in hyperonic ones. As a specific model for MBE, the repulsive multi-pomeron exchange potential (MPP) is added to the two-body interaction together with the phenomenological three-body attraction. For various versions of the Nijmegen interaction models, the MBE parts are determined so as to reproduce the observed data of BΛ. The mass dependence of BΛ values is shown to be reproduced well by adding MBE with the strong MPP repulsion assuring the stiff EoS of hyperon-mixed neutron-star matter, when P -state components of the adopted interaction model lead to almost vanishing contributions. The nuclear matter ΛN G-matrix interactions are derived and used in Λ hypernuclei on the basis of the averaged-density approximation (ADA). The BΛ values of hypernuclei with 9 ≤ A ≤ 59 are analyzed in the framework of Antisymmetrized Molecular Dynamics with use of the two types of ΛN G-matrix interactions including strong and weak MPP repulsions. The calculated values of BΛ reproduce the experimental data finely within a few hundred keV. The values of BΛ in p-states also can be reproduced well, when ADA is modified to be suitable also to weakly-bound Λ states.

The positive-parity states of 25 Mg with a hyperon in s orbit were studied with the antisymmetrized molecular dynamics for hypernuclei. We discuss two bands of 25 Mg corresponding to the K π = 0 + and 2 + bands of 24 Mg. It is found that the energy of the K π = 2 + ⊗ s band is shifted up by about 200 keV compared to 24 Mg. This is because the hyperon in s orbit reduces the quadrupole deformation of the K π = 0 + ⊗ s band, while it does not change the deformation of the K π = 2 + ⊗ s band significantly.

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