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arXiv · 1502.03030

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

U. Forsberg·D. Rudolph·L. -L. Andersson·A. Di Nitto·Ch. E. Düllmann·J. M. Gates·P. Golubev·K. E. Gregorich·C. J. Gross·R. -D. Herzberg·F. P. Hessberger·J. Khuyagbaatar·J. V. Kratz·K. Rykaczewski·L. G. Sarmiento·M. Schädel·A. Yakushev·S. Åberg·D. Ackermann·M. Block·H. Brand·B. G. Carlsson·D. Cox·X. Derkx·J. Dobaczewski·K. Eberhardt·J. Even·C. Fahlander·J. Gerl·E. Jäger·B. Kindler·J. Krier·I. Kojouharov·N. Kurz·B. Lommel·A. Mistry·C. Mokry·W. Nazarewicz·H. Nitsche·J. P. Omtvedt·P. Papadakis·I. Ragnarsson·J. Runke·H. Schaffner·B. Schausten·Y. Shi·P. Thörle-Pospiech·T. Torres·T. Traut·N. Trautmann·A. Türler·A. Ward·D. E. Ward·N. Wiehl
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Abstract

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 f\"ur Schwerionenforschung. 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 are similar to four such events reported from experiments performed at the Dubna gas-filled separator. Contrary to their interpretation, we propose an alternative view, namely to assign eight of these eleven decay chains of recoil-alpha(-alpha)-fission type to start from the 3n-evaporation channel 115-288. The other three decay chains remain viable candidates for the 2n-evaporation channel 115-289.

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U. Forsberg, D. Rudolph, L. -L. Andersson, A. Di Nitto, Ch. E. Düllmann, J. M. Gates, P. Golubev, K. E. Gregorich, C. J. Gross, R. -D. Herzberg, F. P. Hessberger, J. Khuyagbaatar, J. V. Kratz, K. Rykaczewski, L. G. Sarmiento, M. Schädel, A. Yakushev, S. Åberg, D. Ackermann, M. Block, H. Brand, B. G. Carlsson, D. Cox, X. Derkx, J. Dobaczewski, K. Eberhardt, J. Even, C. Fahlander, J. Gerl, E. Jäger, B. Kindler, J. Krier, I. Kojouharov, N. Kurz, B. Lommel, A. Mistry, C. Mokry, W. Nazarewicz, H. Nitsche, J. P. Omtvedt, P. Papadakis, I. Ragnarsson, J. Runke, H. Schaffner, B. Schausten, Y. Shi, P. Thörle-Pospiech, T. Torres, T. Traut, N. Trautmann, A. Türler, A. Ward, D. E. Ward, N. Wiehl. 2015-02-10. Recoil-alpha-fission and recoil-alpha-alpha-fission events observed in the reaction Ca-48 + Am-243. https://doi.org/10.1016/j.nuclphysa.2016.04.025

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