J. M. Gates et al.
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{"title":"Towards the discovery of new elements: Production of livermorium (Z=116) with 50Ti","authors":"J. M. Gates et al.","doi":"10.1103/physrevlett.133.172502","DOIUrl":null,"url":null,"abstract":"<p>The <sup>244</sup>Pu(<sup>50</sup>Ti,<em>xn</em>)<sup>294−x</sup>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≥114 by irradiating an actinide target with a beam heavier than <sup>48</sup>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 <sup>290</sup>Lv. The production cross section was measured to be <span style=\"color: rgb(34, 34, 34); font-family: "Helvetica Neue", Helvetica, Roboto, Arial, sans-serif; font-size: 14px; text-wrap: wrap; background-color: rgb(255, 255, 255);\"> </span><mjx-container class=\"MathJax CtxtMenu_Attached_0\" jax=\"CHTML\" overflow=\"linebreak\" sre-explorer-id=\"39\" tabindex=\"0\" role=\"tree\" ctxtmenu_oldtabindex=\"1\" ctxtmenu_counter=\"39\" style=\"box-sizing: border-box; color: rgb(34, 34, 34); font-family: "Helvetica Neue", Helvetica, Roboto, Arial, sans-serif; background-color: rgb(255, 255, 255); font-size: 13.846px;\"><mjx-math data-semantic-structure=\"(22 (18 (2 0 1) 3 4) (13 (12 5 (8 6 7)) (11 9 10)) 14 (21 15 16 17))\" class=\"STX-N\" style=\"box-sizing: border-box; display: inline-block; line-height: 0; font-size: 13.846px; font-size-adjust: none; overflow-wrap: normal; word-spacing: normal; direction: ltr; padding: 1px 0px; font-family: MJX-STX-ZERO, MJX-STX-N;\"><mjx-mrow data-semantic-type=\"punctuated\" data-semantic-role=\"sequence\" data-semantic-id=\"22\" data-semantic-children=\"18,13,14,21\" data-semantic-content=\"13,14\" data-semantic-owns=\"18 13 14 21\" data-semantic-speech=\"sigma Subscript p r o d Baseline equals 0.44 left parenthesis Subscript negative 0.28 Superscript plus 0.58 Baseline right parenthesis p b\" style=\"box-sizing: border-box; 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display: inline-block; font-family: MJX-STX-ZERO, "Helvetica Neue", Helvetica, Roboto, Arial, sans-serif;\"><mjx-utext variant=\"-explicitFont\" style=\"box-sizing: border-box; display: inline-block; padding: 0.813em 0px 0.217em; font-size: 12.7799px; width: 3px;\"> </mjx-utext></mjx-mtext></mjx-mrow></mjx-mrow></mjx-math></mjx-container>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 <sup>50</sup>Ti and is an essential precursor in the pursuit of searching for new elements beyond Z=118.</p>","PeriodicalId":20069,"journal":{"name":"Physical review letters","volume":null,"pages":null},"PeriodicalIF":8.1000,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physical review letters","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1103/physrevlett.133.172502","RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"PHYSICS, MULTIDISCIPLINARY","Score":null,"Total":0}
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