Experiment on the synthesis of element 113 in the reaction 209Bi(70Zn,n)278113

Abstract

The convincing candidate event of the isotope of the 113th element, 278113, and its daughter nuclei, 274111 and 270Mt, were observed, for the first time, in the 209Bi + 70Zn reaction at a beam energy of 349.0 MeV with a total dose of 1.7 × 1019. Alpha decay energies and decay times of the candidates, 278113, 274111, and 270Mt, were (11.68 ± 0.04 MeV, 0.344 ms), (11.15 ± 0.07 MeV, 9.26ms), and (10.03 ± 0.07 MeV, 7.16 ms), respectively. The production cross section of the isotope was deduced to be 55-45+150 fb(10-39 cm2). © 2004 The Physical Society of Japan.