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Two distinct quasifission modes in the 32S + 232Th reaction
D J Hinde1, R du Rietz, M Dasgupta
1Department of Nuclear Physics, Research School of Physical Sciences and Engineering, The Australian National University, Canberra, ACT 0200, Australia.
Physical Review Letters
|October 15, 2008
Summary
Measurements of sulfur-32 reacting with thorium-232 reveal two surprising quasifission components. Their probabilities shift with energy, indicating a link to nuclear deformation at contact.
Area of Science:
- Nuclear Physics
- Heavy-ion Reactions
- Nuclear Fission
Background:
- Understanding nuclear fission dynamics is crucial for nuclear energy and astrophysics.
- Investigating reactions with deformed nuclei provides insights into nuclear structure effects on reaction outcomes.
Purpose of the Study:
- To comprehensively measure fission properties for the 32S + 232Th reaction at near-barrier energies.
- To analyze mass-angle distributions to identify reaction mechanisms.
- To explore the influence of nuclear deformation on quasifission probabilities.
Main Methods:
- Performed comprehensive fission measurements, including mass-angle distributions.
- Studied the reaction of sulfur-32 (32S) with the prolate deformed nucleus thorium-232 (232Th).
- Analyzed data at near-barrier energies.
Main Results:
- Observed two distinct components in both mass and angle distributions.
- Surprisingly, both components exhibited characteristics of quasifission.
- Found that the relative probabilities of these components varied rapidly with the beam energy to capture barrier ratio.
Conclusions:
- The observed quasifission characteristics suggest complex dynamics in the 32S + 232Th system.
- The rapid variation in component probabilities indicates a strong dependence on the energy and potentially nuclear deformation.
- Results imply a relationship between fission characteristics and aligned/antialigned deformation configurations at nuclear contact.
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