Spectroscopy of Element 115 Decay Chains

A high-resolution , X-ray and gamma-ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum fur Schwerionenforschung. Thirty correlated alpha- decay chainswere detected following the fusion-evaporation reaction 48Ca + 243Am. The observations are consistent with previous assignments of similar decay chainsto originate from element Z = 115. For the first time, precise spectroscopy allows the derivation of excitation schemes of isotopes along the decay chainsstarting with elements Z > 112. Comprehensive Monte-Carlo simulations accompany the data analysis. Nuclear structuremodels provide a first level interpretation.