Experiment on the Synthesis of Element 113 in the Reaction²⁰⁹Bi(⁷⁰Zn,n)²⁷⁸113

The convincing candidate event of the isotope of the 113th element, 278 113, and its daughter nuclei, 274 111 and 270 Mt, were observed, for the first time, in the 209 Bi + 70 Zn reaction at a beam energy of 349.0 MeV with a total dose of 1.7 ×10 19 . Alpha decay energies and decay times of the candidates, 278 113, 274 111, and 270 Mt, were (11.68 ±0.04 MeV, 0.344 ms), (11.15 ±0.07 MeV, 9.26 ms), and (10.03 ±0.07 MeV, 7.16 ms), respectively. The production cross section of the isotope was deduced to be 55 +150 -45 fb (10 -39 cm 2 ).