Structure and spectroscopy of transcurium nuclei

The stability of the superheavy elements depends on the shell corrections which are governed by the single-particle spectra. Ideally one would like to experimentally determine the single-particle levels in the superheavy nuclei but the production of only a few atoms of these nuclides precludes such measurements. One therefore has to identify single-particle levels in the heaviest nuclei which are available in at least nanoCurie amounts. They have studied the structure of such heavy nuclei in the Z=98 region and identified many single-particle states. In particular, they have studied the structure of 251Cf and 249Bk by measuring the radiations emitted in the α decay of 255Fm and 253Es. These single-particle spectra can be used to test theoretical models for superheavy elements