Three-body forces and proton-rich nuclei

Area of Science:

• Nuclear Physics
• Quantum Chromodynamics
• Effective Field Theory

Background:

• Three-nucleon (3N) forces are crucial for understanding nuclear structure and stability.
• Proton-rich nuclei near the dripline present unique challenges for theoretical models.
• Chiral effective field theory provides a framework for systematically constructing nuclear forces.

Purpose of the Study:

• To investigate the impact of three-nucleon forces on the properties of proton-rich nuclei.
• To predict ground-state energies, separation energies, and excitation spectra for N=8 and N=20 isotones.
• To test the predictive power of nuclear forces derived from chiral effective field theory.

Main Methods:

• Ab initio calculations employing state-of-the-art nuclear forces.
• Systematic study of N=8 and N=20 isotone chains up to the proton dripline.
• Comparison of theoretical predictions with experimental data and the isobaric multiplet mass equation.

Main Results:

• Ground-state and proton separation energies show excellent agreement with experimental data where available.
• Predicted excitation spectra for several isotopes (e.g., 18Ne, 19Na, 20Mg, 42Ti) are in good accord with experimental observations.
• First theoretical predictions are provided for isotopes where experimental data is currently lacking.

Conclusions:

• Three-nucleon forces play a significant role in accurately describing proton-rich nuclei.
• The employed nuclear forces derived from chiral effective field theory demonstrate strong predictive power.
• These findings pave the way for future studies of isospin symmetry breaking in medium-mass nuclei.