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Toward the Discovery of New Elements: Production of Livermorium ( $Z = 116$ ) with ${}^{50}{Ti}$

J. M. Gates ^1,*, R. Orford¹, D. Rudolph^2,1, C. Appleton¹, B. M. Barrios³, J. Y. Benitez¹, M. Bordeau⁴, W. Botha³, C. M. Campbell¹ et al.

J. Chadderton⁵, A. T. Chemey⁶, R. M. Clark¹, H. L. Crawford¹, J. D. Despotopulos⁷, O. Dorvaux⁴, N. E. Esker³, P. Fallon¹, C. M. Folden, III^8,9, B. J. P. Gall⁴, F. H. Garcia^1,†, P. Golubev^2,1, J. A. Gooding^1,10, M. Grebo^1,10, K. E. Gregorich⁷, M. Guerrero³, R. A. Henderson⁷, R.-D. Herzberg⁵, Y. Hrabar², T. T. King¹¹, M. Kireeff Covo¹, A. S. Kirkland^8,9, R. Krücken¹, E. Leistenschneider¹, E. M. Lykiardopoulou¹, M. McCarthy^1,10, J. A. Mildon^8,9, C. Müller-Gatermann¹², L. Phair¹, J. L. Pore¹, E. Rice^1,10, K. P. Rykaczewski¹¹, B. N. Sammis⁷, L. G. Sarmiento², D. Seweryniak¹², D. K. Sharp¹³, A. Sinjari^1,10, P. Steinegger^14,15, M. A. Stoyer^7,1, J. M. Szornel¹, K. Thomas⁷, D. S. Todd¹, P. Vo³, V. Watson¹, and P. T. Wooddy⁷

¹Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
²Department of Physics, Lund University, 22100 Lund, Sweden
³San Jose State University, San Jose, California 95192, USA
⁴Université de Strasbourg, CNRS, IPHC UMR 7178, 67037 Strasbourg, France
⁵University of Liverpool, Liverpool, United Kingdom
⁶Oregon State University, Corvallis, Oregon 97331, USA
⁷Lawrence Livermore National Laboratory, Livermore, California 94550, USA
⁸Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA
⁹Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA
¹⁰University of California, Berkeley, California 94720, USA
¹¹Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
¹²Argonne National Laboratory, Lemont, Illinois 60439, USA
¹³University of Manchester, Manchester, United Kingdom
¹⁴Department of Chemistry and Applied Biosciences, ETH Zürich, Zurich, Switzerland
¹⁵Nuclear Energy and Safety Division, Paul Scherrer Institute, Villigen PSI, Switzerland

^*Contact author: jmgates@lbl.gov
^†Present address: Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.

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Phys. Rev. Lett. 133, 172502 – Published 21 October, 2024

DOI: https://doi.org/10.1103/PhysRevLett.133.172502

Abstract

The ${}^{244}{Pu} ({}^{50}{Ti}, x n) {}^{294 - x}{Lv}$ reaction was investigated at Lawrence Berkeley National Laboratory’s 88-Inch Cyclotron. The experiment was aimed at the production of a superheavy element with $Z \geq 114$ by irradiating an actinide target with a beam heavier than ${}^{48}{Ca}$ . 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 ${}^{290}{Lv}$ . The production cross section was measured to be $σ_{prod} = 0.44 (_{- 0.28}^{+ 0.58}) pb$ 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 ${}^{50}{Ti}$ and is an essential precursor in the pursuit of searching for new elements beyond $Z = 118$ .

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A Route Toward the Island of Stability

Published 21 October, 2024

Scientists have synthesized an isotope of the superheavy element livermorium using a novel fusion reaction. The result paves the way for the discovery of new chemical elements.

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Toward the Discovery of New Elements: Production of Livermorium ( $Z = 116$ ) with ${}^{50}{Ti}$