Global Microscopic Description of Nucleon-Nucleus Scattering with Quantified Uncertainties

Area of Science:

• Nuclear Physics
• Quantum Chromodynamics
• Nuclear Astrophysics

Background:

• Accurate nucleon-nucleus optical potentials are crucial for interpreting nuclear reaction experiments.
• Existing potentials often lack quantified uncertainties or are not universally applicable across a wide range of nuclei and energies.
• Next-generation rare-isotope beam facilities require sophisticated theoretical tools for precise reaction analysis.

Purpose of the Study:

• To develop the first microscopic global nucleon-nucleus optical potential with quantified uncertainties.
• To provide a reliable tool for analyzing nuclear reaction experiments at future rare-isotope beam facilities.
• To enable accurate predictions of nucleon scattering on both stable and unstable isotopes.

Main Methods:

• Utilizing the improved local density approximation and five nuclear forces from chiral effective field theory.
• Computing proton-nucleus and neutron-nucleus optical potentials for 1800 target nuclei (12≤A≤242) across a broad energy range (0 < E ≲ 150 MeV).
• Parameterizing global optical potentials dependent on projectile energy, target mass number, and isospin asymmetry, incorporating a full covariance analysis for uncertainty quantification.

Main Results:

• A global optical potential was derived for each chiral force, smoothly dependent on nuclear properties and energy.
• Quantified uncertainties were generated for elastic scattering observables, validated against experimental data for stable nuclei.
• The microscopic approach demonstrates potential for high accuracy in predicting scattering on unstable isotopes.

Conclusions:

• The developed microscopic global optical potential offers quantified uncertainties, essential for nuclear reaction studies.
• This model is suitable for analyzing experiments at next-generation rare-isotope beam facilities.
• The purely microscopic nature suggests reliable predictions for scattering involving unstable nuclei, advancing nuclear structure and reaction studies.