Towards the discovery of new elements: Production of livermorium (Z=116) with 50Ti

Abstract

The ²⁴⁴Pu(⁵⁰Ti,xn)^294−xLv reaction was investigated at Lawrence Berkeley National Laboratory's 88-Inch Cyclotron. The experiment was aimed at the production of a superheavy element with Z≥114 by irradiating an actinide target with a beam heavier than ⁴⁸Ca. Produced Lv ions were separated from the unwanted beam and nuclear reaction products using the Berkeley Gas-filled Separator and implanted into a newly commissioned focal plane detector system. Two decay chains were observed and assigned to the decay of ²⁹⁰Lv. The production cross section was measured to be  𝜎prod=0.44(+0.58−0.28)  pb at a center-of-target center-of-mass energy of 220(3)~MeV. This represents the first published measurement of the production of a superheavy element near the `Island-of-Stability’, with a beam of ⁵⁰Ti and is an essential precursor in the pursuit of searching for new elements beyond Z=118.