Modification of triaxial deformation and change of spectrum in $^{25}_{\ ��}$Mg caused by $��$ hyperon
説明
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 $K^��=0^+$ and $2^+$ bands of $^{24}$Mg. It is found that the energy of the $K^��= 2^+ \otimes ��_s$ 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 $K^��= 0^+ \otimes ��_s$ band, while it does not change the deformation of the $K^��= 2^+ \otimes ��_s$ band significantly.
19 pages, 3 figures