New Insights into the ^{243}Am+^{48}Ca Reaction Products Previously Observed in the Experiments on Elements 113, 115, and 117 (original) (raw)

Abstract

Results of a new series of experiments on the study of production cross sections and decay properties of the isotopes of element 115 in the reaction 243 Am þ 48 Ca are presented. Twenty-one new decay chains originating from 288 115 were established as the product of the 3n-evaporation channel by measuring the excitation function at three excitation energies of the compound nucleus 291 115. The decay properties of all newly observed nuclei are in full agreement with those we measured in 2003. At the lowest excitation energy E Ã ¼ 33 MeV, for the first time we registered the product of the 2n-evaporation channel, 289 115, which was also observed previously in the reaction 249 Bk þ 48 Ca as the daughter nucleus of the decay of 293 117. The maximum cross section for the production of 288 115 is found to be 8.5 pb at E Ã % 36 MeV.

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