Zeitschrift für Physik A Atomic Nuclei

, Volume 333, Issue 2, pp 163–175

Element 107

  • G. Münzenberg
  • P. Armbruster
  • S. Hofmann
  • F. P. Heßberger
  • H. Folger
  • J. G. Keller
  • V. Ninov
  • K. Poppensieker
  • A. B. Quint
  • W. Reisdorf
  • K. -H. Schmidt
  • J. R. H. Schneider
  • H. -J. Schött
  • K. Sümmerer
  • I. Zychor
  • M. E. Leino
  • D. Ackermann
  • U. Gollerthan
  • E. Hanelt
  • W. Morawek
  • D. Vermeulen
  • Y. Fujita
  • T. Schwab
Heavy Ion Physics, Fission

DOI: 10.1007/BF01565147

Cite this article as:
Münzenberg, G., Armbruster, P., Hofmann, S. et al. Z. Physik A - Atomic Nuclei (1989) 333: 163. doi:10.1007/BF01565147

Abstract

We identified twoα-emitting isotopes of element 107 with masses of 261 and 262 respectively by parent-daughter correlations. For the isotope with mass 262 we found two transitions with (102±26) ms and (8.0±2.1) ms half-life, which we assign to the groundstate and to an isomeric transition, respectively. The half-life of the isotope with mass 261 is (11.8−2.8+5.3) ms. Spontaneous fission, which could be assigned to the decay of an isotope of element 107, was not detected in our experiments. This observation is in-line with our previous results, indicating a region of nuclei with strong microscopic stabilisation in the trans-actinides. Both new isotopes were produced by complete fusion of209Bi with54Cr. The production cross sections are (163±34) pb for262107 and (36−14+22) pb for261107.

PACS

23.60.+e25.70.3f25.85.Ca27.9.+6

Copyright information

© Springer-Verlag 1989

Authors and Affiliations

  • G. Münzenberg
    • 1
  • P. Armbruster
    • 1
  • S. Hofmann
    • 1
  • F. P. Heßberger
    • 1
  • H. Folger
    • 1
  • J. G. Keller
    • 1
  • V. Ninov
    • 1
  • K. Poppensieker
    • 1
  • A. B. Quint
    • 1
  • W. Reisdorf
    • 1
  • K. -H. Schmidt
    • 1
  • J. R. H. Schneider
    • 1
    • 2
  • H. -J. Schött
    • 1
  • K. Sümmerer
    • 1
  • I. Zychor
    • 1
    • 3
  • M. E. Leino
    • 4
  • D. Ackermann
    • 5
  • U. Gollerthan
    • 5
  • E. Hanelt
    • 5
  • W. Morawek
    • 5
  • D. Vermeulen
    • 5
    • 6
  • Y. Fujita
    • 7
  • T. Schwab
    • 7
  1. 1.Gesellschaft für Schwerionenforschung mbHDarmstadtFederal Republic of Germany
  2. 2.Department of PhysicsUniversity of HelsinkiHelsinkiFinland
  3. 3.Institut für KernphysikTH DarmstadtFederal Republic of Germany
  4. 4.II. Physikalisches InstitutUniversität GießenFederal Republic of Germany
  5. 5.Institute for Nuclear StudiesSwierkPoland
  6. 6.Motorola GmbHFrankfurt/MainFederal Republic of Germany
  7. 7.Schweizerisches Institut für Nuklearforschung SINZürichSwitzerland
  8. 8.College of General EducationOsaka UniversityOsakaJapan