Synthesis of a New Element with Atomic Number Z=117

Joint Institute for Nuclear Research, RU-141980 Dubna, Russian Federation.
Physical Review Letters (Impact Factor: 7.51). 04/2010; 104(14):142502. DOI: 10.1103/PhysRevLett.104.142502
Source: PubMed


The discovery of a new chemical element with atomic number Z=117 is reported. The isotopes (293)117 and (294)117 were produced in fusion reactions between (48)Ca and (249)Bk. Decay chains involving 11 new nuclei were identified by means of the Dubna gas-filled recoil separator. The measured decay properties show a strong rise of stability for heavier isotopes with Z > or = 111, validating the concept of the long sought island of enhanced stability for superheavy nuclei.

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