Recoil-α-fission and recoil-α-α-fission events observed in the reaction 48Ca+243Am

Products of the fusion-evaporation reaction Ca-48 + Am-243 were studied with the TASISpec set-up at the gas-filled separator TASCA at the GSI Helmholtzzentrum fur Schwerionenforschung, Darmstadt, Germany. Amongst the detected thirty correlated alpha-decay chains associated With the production of element Z = 115, two recoil-alpha-fission and five recoil-alpha-alpha-fission events were observed. The latter five chains are similar to four such events reported from experiments performed at the Dubna gas-filled separator, and three such events reported from an experiment at the Berkeley gas-filled separator. The four chains observed at the Dubna gas-filled separator were assigned to start from the 2n-evaporation channel (289)115 due to the fact that these recoil-alpha-alpha-fission events were observed only at low excitation energies. Contrary to this interpretation, we suggest that some of these recoil-alpha-alpha-fission decay chains, as well as some of the recoil-alpha-alpha-fission and recoil-alpha-fission decay chains reported from Berkeley and in this article, start from the 3n-evaporation channel (288)115. (C) 2016 Elsevier B.V. All rights reserved.