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Precision Determination of Pion-Nucleon Coupling Constants Using Effective Field Theory
P Reinert1, H Krebs1, E Epelbaum1
1Ruhr-Universität Bochum, Fakultät für Physik und Astronomie, Institut für Theoretische Physik II, D-44780 Bochum, Germany.
Physical Review Letters
|March 22, 2021
Summary
This study precisely determined pion-nucleon coupling constants, crucial for nuclear forces, using advanced chiral effective field theory methods. Results show no significant charge dependence, advancing nuclear physics understanding.
Area of Science:
- Nuclear Physics
- Quantum Chromodynamics
- Particle Physics
Background:
- Pion-nucleon coupling constants govern long-range nuclear forces.
- Isospin symmetry suggests similar couplings, but quark masses and EM effects may cause differences.
- Previous determinations of these constants are deficient.
Purpose of the Study:
- To precisely determine pion-nucleon coupling constants.
- To control uncertainties in these fundamental observables.
- To investigate charge dependence of these couplings.
Main Methods:
- Utilized neutron-proton and proton-proton scattering data.
- Employed chiral effective field theory (ChEFT).
- Implemented a Bayesian approach for a novel partial-wave analysis up to the pion production threshold, including isospin-breaking effects.
Main Results:
- Achieved percent-level accuracy for pion-nucleon coupling constants.
- Demonstrated no significant charge dependence in the determined values.
- Provided mutually consistent scattering data.
Conclusions:
- The results represent a significant advancement in precision nuclear force theory.
- The findings contribute to a better understanding of nuclear structure.
- This work paves the way for more accurate nuclear models.
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