Simultaneous Determination of Neutron-Induced Fission and Radiative Capture Cross Sections from Decay Probabilities...

Area of Science:

• Nuclear Physics
• Nuclear Astrophysics
• Radiative Capture and Fission Reactions

Background:

• Direct measurement of neutron-induced reaction cross sections for unstable nuclei is often impossible.
• The surrogate-reaction method is a key alternative for obtaining these essential nuclear data.
• Accurate cross sections are vital for understanding stellar nucleosynthesis and nuclear applications.

Purpose of the Study:

• To apply the surrogate-reaction method to infer neutron-induced fission and radiative capture cross sections of Plutonium-239.
• To achieve a consistent determination of both cross sections from a single measurement.
• To expand the applicability of the surrogate-reaction method by measuring gamma-emission probability.

Main Methods:

• Utilized the ^{240}Pu(^{4}He,^{4}He^{'}) reaction as a surrogate.
• Simultaneously measured fission and gamma-emission probabilities.
• Combined experimental data with calculations of angular-momentum and parity distributions.

Main Results:

• Successfully inferred both neutron-induced fission and radiative capture cross sections of ^{239}Pu for the first time.
• Demonstrated the consistent determination of these cross sections from a single surrogate measurement.
• Measured the overall gamma-emission probability, unlike previous experiments focusing on specific transitions.

Conclusions:

• The surrogate-reaction method, as applied in this study, provides a viable and consistent pathway to determine crucial nuclear reaction cross sections.
• This work significantly enhances the utility and applicability of the surrogate-reaction method for nuclear astrophysics and applications.
• The ability to measure gamma-emission probability broadens the scope of nuclei accessible via this technique.