Toward the Discovery of New Elements: Production of Livermorium ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>Z</mml:mi><mml:mo>=</mml:mo><mml:mn>116</mml:mn></mml:mrow></mml:math> ) with <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mmultiscripts><mml:mrow><mml:mi>Ti</mml:mi></mml:mrow><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>50</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow></mml:math>

Abstract

The Pu244(Ti50,xn)Lv294-x 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 Ca48. 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 Lv290. The production cross section was measured to be σprod=0.44(-0.28+0.58) 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 Ti50 and is an essential precursor in the pursuit of searching for new elements beyond Z=118