Superdeformation around 144Gd

The study of superdeformation in nuclei around the nucleus Gd-144, 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 Gd-143. Since highly-deformed bands are known in Gd-139,Gd-141, it appears that the transition between the regions of superdeformed nuclei with A approximate to 150 and of highly-deformed nuclei with A approximate to 130 is lather sharp and takes place around N = 78 as theoretically predicted. In Gd-144 four excited superdeformed bands have been found in addition to the yrast superdeformed band. They form two pairs of signature partner bands of pi 6(1) pi[404]9/2 nu 7 degrees and pi 6(1) pi[411]3/2 nu 7 degrees configurations. In Gd-145 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]1/2 neutron orbitals, respectively.