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Characterizing Neutron-Proton Equilibration in Nuclear Reactions with Subzeptosecond Resolution
A Jedele1,2, A B McIntosh1, K Hagel1
1Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA.
Physical Review Letters
|February 25, 2017
Summary
Neutron-proton equilibration in atomic nuclei occurs rapidly on a subzeptosecond timescale. This study reveals insights into the nuclear equation of state, crucial for understanding chemical element origins.
Area of Science:
- Nuclear Physics
- Nuclear Astrophysics
Background:
- Atomic nuclei created in nuclear collisions can be dynamically deformed.
- These deformed nuclei initially have dissimilar compositions at their ends.
Purpose of the Study:
- To investigate the neutron-proton equilibration process in dynamically deformed atomic nuclei.
- To determine the timescale and kinetics of this equilibration.
Main Methods:
- Studying neutron-proton equilibration in dynamically deformed nuclei from nuclear collisions.
- Utilizing angular momentum to correlate nuclear breakup orientation with its timescale.
- Applying first-order kinetics to model the equilibration process.
Main Results:
- Equilibration occurs on a subzeptosecond timescale.
- The extracted rate constant for equilibration is 3 zs⁻¹.
- This corresponds to a mean equilibration time of 0.3 zs.
Conclusions:
- The rapid equilibration provides new insights into the nuclear equation of state.
- Understanding the nuclear equation of state is vital for nuclear and astrophysical phenomena.
- This research contributes to understanding the origin of chemical elements.
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