Study of the properties of the superheavy nuclei Z = 117 produced in the super(249)Bk + super(48)Ca reaction

• Published in: EPJ Web of conferences Vol. 66; pp. 02073 - 1-02073-4
• Main Authors: Oganessian, Yu Ts, Abdullin, F Sh, Alexander, C, Binder, J, Boll, R A, Dmitriev, S N, Ezold, J, Felker, K, Gostic, J M, Grzywacz, R K
• Format: Journal Article
• Language: English
• Published: 01.01.2014
• Subjects: Beams (radiation); Channels; Decay; Excitation; Isotopes; Nuclei; Projectiles; Spectra
• ISSN: 2100-014X
• DOI: 10.1051/epjconf/20146602073

The reaction of super(249)Bk with super(48)Ca have been reinvestigated to provide new evidence for the discovery of element 117 on a larger number of events. The experiments were performed at five projectile energies and with a total beam dose of super(48)Ca of about 4.6 x l0 super(19). Two isotopes super(293,294)117 were synthesized in the super(249)Bk + super(48)Ca reaction, providing excitation functions and alpha -decay spectra of the produced isotopes that establishes these nuclei to be the products of the 4n- and 3n-evaporation channels, respectively. Decay properties of super(293,294)117 and of all the daughter products agree with the data of the experiment in which these nuclei were synthesized for the first time in 2010. The new super(289)115 events, populated by alpha decay of super(293)117, demonstrate the same decay properties as those observed for super(289)115 produced in the super(243)Am( super(48)Ca, 2n) reaction thus providing cross-bombardment evidence. In addition, a single decay of super(294)118 was observed from the reaction with super(249)Cf - a result of the in-growth of super(249)Cf in the super(249)Bk target.