Elsevier

Nuclear Physics A

Volume 160, Issue 1, 4 January 1971, Pages 181-192
Nuclear Physics A

On the synthesis of element 105

https://doi.org/10.1016/0375-9474(70)90182-XGet rights and content

Abstract

In bombardments of a 243Am target with 22Ne ions a spontaneous fission activity with a half-life of {ce:inline-formula}1.8±0.6s{/ce:inline-formula} has been observed. The yield corresponds to a formation cross section of {ce:inline-formula}(5.0±1.5) × 10 −34cm 2{/ce:inline-formula}, for the spontaneous fission decay.

Integral angular distributions of products from the reaction 243Am + 22Ne and the formation cross section for the new isotope as a function of the bombarding ion energy have been measured. From these data and the results of test experiments it is concluded that the atomic number of the new spontaneous fission activity with {ce:inline-formula}T 1/2≈ 2s{/ce:inline-formula}, is 105.

The spontaneous fission decay of the isotopes 256,257103 has also been investigated. The spontaneous fission half-lives of these nuclei are shown to be larger than 10 5 s.

Reference (25)

  • OganesianYu.Ts. et al.

    Preprint JINR P7-4637

    (1969)
  • FlerovG.N. et al.

    Preprint JINR P7-3808

    (1968)
  • AkapievG.N. et al.

    Preprint JINR P7-4772

    (1970)
  • LedererC.M. et al.

    Table of isotopes

    (1967)
  • KapuscikA. et al.

    Prib. Tekhn. Eksp.

    (1964)
  • PolikanovS.M. et al.LarkN.L. et al.

    Nucl. Phys.

    (1969)
  • DruinV.A. et al.

    Preprint JINR 1670

    (1964)
  • SimonoffG.N. et al.

    Report UCRL-10099

    (1962)
  • KumpfG. et al.

    JETP (Sov. Phys.)

    (1963)
  • DruinV.A. et al.

    Preprint JINR P7-4681

    (1969)
  • OganesianYu.Ts. et al.

    Atomn. Energ.

    (1970)
  • FlerovG.N. et al.

    Communications of the JINR, P7-4932

    (February 1970)
  • Cited by (42)

    • Discovery of isotopes of elements with Z≥100

      2013, Atomic Data and Nuclear Data Tables
    • TASISpec-A highly efficient multi-coincidence spectrometer for nuclear structure investigations of the heaviest nuclei

      2010, Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
      Citation Excerpt :

      Experimental studies of very heavy or superheavy nuclei have challenged scientists for decades and the ability to produce new and heavier elements has continuously improved through the second half of the 20th century. For instance, the discovery of element Z=100 was published in the 1950s [1], Z=105 in the 1970s [2], Z=110 in the 1990s [3], and Z=118—the heaviest element claimed so far—in the 2000s [4]. In order to keep up with the growing demand for experimental data on the heaviest elements, recoil separators have been built at different accelerator facilities around the world.

    View all citing articles on Scopus
    View full text