Atomic mass measurements and nuclear spectroscopy at TRISTAN. Progress report, February 1, 1981-January 31, 1982

The research program is concerned with measuring atomic masses and decay schemes of short-lived, neutron-rich fission products using the TRISTAN on-line mass separator located at the High Flux Beam Reactor (HFBR), Brookhaven National Laboratory. The determination of accurate masses for neutron-rich nuclei is useful in testing and refining mass equations which, in turn, find important application in calculations of astrophysical processes and for control and safety of nuclear reactors. The thrust of the spectroscopic studies has been to develop a data base for neutron-rich, far-from-stability nuclides in order to provide a new testing ground for nuclear models. In particular, we have been active in pursuing microscopic and phenomenological understanding of nuclear structure in regions of shape transition near shell and subshell closures