Polarization of ~4He in _Λ~5He

摘要

Variational calculations for s-shell hypernuclei are performed by explicitly including Σ degrees of freedom. Two sets of YN interactions (D2 and SC97e(S)) are used. The bound-state solution of _Λ~5He is obtained by using each of YN potentials, and a large energy expectation value of the tensor ΛN - ΣN transition part is found by using the SC97e(S). The internal energy of the ~4He subsystem changes a lot by the presence of a Λ particle with the strong tensor ΛN - ΣN transition potential.