Structure of neutron-rich Br and Nb nuclei populated in fission experiments

Abstract

Spectroscopic information on exotic Br and Nb nuclei, with odd and even masses around A=100, respectively, was obtained by analyzing fission fragments data collected with AGATA+VAMOS++ at GANIL and the FIPPS spectrometer at ILL. The complementarity of these two state-of-the art setups has been used, for the first time, to investigate the structure of these neutron-rich fission fragments via gamma-ray spectroscopy. Details on the two fission experiments will be given, as well as examples of high-resolution gamma-ray spectra used for the reconstruction of the level schemes. The active fission target, used in the neutron-induced fission experiment at ILL, allowed for high-statistics prompt-delayed coincidences for the analysis of a new isomeric state in 100Nb. Evidence for a spherical isomeric state in 100Nb will be shown and discussed within the systematic of neighbouring nuclei.