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Prediction for a Four-Neutron Resonance
A M Shirokov1,2,3, G Papadimitriou4, A I Mazur3
1Skobeltsyn Institute of Nuclear Physics, Moscow State University, Moscow 119991, Russia.
Physical Review Letters
|November 12, 2016
Summary
Researchers explored the four-neutron (4n) system, predicting a low-lying resonance. This neutron resonance state was found near 0.8 MeV with a width of 1.4 MeV using advanced ab initio methods.
Area of Science:
- Nuclear Physics
- Quantum Mechanics
- Few-Body Systems
Background:
- Understanding the behavior of neutron systems is crucial for nuclear structure and reactions.
- The existence and properties of the four-neutron (4n) system remain an active area of research.
- Investigating few-neutron systems provides insights into the fundamental forces between nucleons.
Purpose of the Study:
- To search for a low-lying resonance in the four-neutron (4n) system.
- To determine the energy and width of any predicted resonant state.
- To employ advanced ab initio computational methods for high accuracy.
Main Methods:
- Utilized various ab initio approaches for theoretical calculations.
- Employed the JISP16 realistic nucleon-nucleon (NN) interaction.
- Applied a J-matrix extension of the no-core shell model for the most accurate prediction.
Main Results:
- Predicted a resonant state in the four-neutron (4n) system.
- The resonance is located at an energy near E_r = 0.8 MeV.
- The predicted resonance has a width of approximately Γ = 1.4 MeV.
Conclusions:
- The study provides strong evidence for the existence of a 4n resonant state.
- The calculated properties of this resonance offer valuable data for nuclear theory.
- Further experimental and theoretical investigations are warranted to confirm these findings.
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