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Updated: Jul 2, 2026
10:42
Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
Fission time measurements: a new probe into superheavy element stability.
M Morjean1, D Jacquet, J L Charvet
1GANIL, CEA-DSM, and IN2P3-CNRS, B.P. 55027, F-14076 Caen Cedex, France. morjean@ganil.fr
Physical Review Letters
|September 4, 2008
Summary
Heavy nuclei with Z=120 and 124, formed in nuclear reactions, show longer lifetimes exceeding 10^-18 seconds. In contrast, neutron-deficient nuclei with Z=114 exhibit shorter, experimentally limited lifetimes.
Area of Science:
- Nuclear Physics
- Heavy Ion Collisions
- Nuclear Reaction Mechanisms
Background:
- Understanding the properties of superheavy nuclei is crucial for testing nuclear models.
- Previous studies have explored the synthesis and decay of elements beyond the actinides.
Purpose of the Study:
- To investigate the reaction mechanisms and lifetimes of nuclei produced in heavy ion collisions.
- To search for evidence of long-lived superheavy nuclei.
Main Methods:
- Utilized a 4pi detector to analyze reaction mechanisms.
- Analyzed reaction time distributions for systems including 208Pb + Ge, 238U + Ni, and 238U + Ge.
- Investigated nuclei with atomic numbers (Z) of 114, 120, and 124.
Main Results:
- Provided evidence for the existence of nuclei with Z=120 and Z=124.
- These nuclei were observed to have lifetimes longer than 10^-18 seconds.
- Neutron-deficient nuclei with Z=114, potentially formed in 208Pb + Ge reactions, showed shorter lifetimes.
Conclusions:
- Highly excited compound nuclei can lead to the formation of relatively long-lived superheavy nuclei.
- The experimental setup is sensitive to nuclear lifetimes on the order of 10^-18 seconds.
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