Superdeformation around ¹⁴⁴Gd

The study of superdeformation in nuclei around the nucleus ¹⁴⁴Gd, which can be considered as doubly-closed at superdeformed shape, provided detailed knowledge about the structure of superdeformed bands in this region. The chain of Gd isotopes showing superdeformation could be extended to ¹⁴³Gd. Since highly-deformed bands are known in ^139,141Gd, it appears that the transition between the regions of superdeformed nuclei with A ≈ 150 and of highly-deformed nuclei with A ≈ 130 is rather sharp and takes place around N = 78 as theoretically predicted. In ¹⁴⁴Gd four excited superdeformed bands have been found in addition to the yrast superdeformed band. They form two pairs of signature partner bands of π6¹ π[404]9/2ν7⁰ and π6¹π[411]3/2ν/7⁰ configurations. In ¹⁴⁵Gd for the first time two crossings have been observed in a superdeformed band, which are assigned to the alignment of an i_13/2 proton pair and a subsequent crossing of the i^13/2 [642]5/2 and i_11/2 [651]l/2 neutron orbitals, respectively.