Pion-Induced Radiative Corrections to Neutron β Decay

Area of Science:

• Nuclear Physics
• Particle Physics
• Quantum Field Theory

Background:

• Neutron beta decay is a fundamental process for studying weak interactions.
• Electromagnetic corrections are crucial for precise theoretical predictions.
• Previous calculations may have missed certain radiative effects.

Purpose of the Study:

• To compute electromagnetic corrections to neutron beta decay.
• To identify and quantify previously overlooked radiative corrections.
• To assess the impact of these corrections on experimental observables.

Main Methods:

• Utilized low-energy hadronic effective field theory.
• Incorporated virtual pion contributions to radiative corrections.
• Analyzed effects on axial charge, angular correlations, and asymmetry.

Main Results:

• Identified new radiative corrections from virtual pions.
• Found a percent-level shift in the nucleon axial charge.
• Quantified smaller corrections affecting angular correlations and asymmetry.

Conclusions:

• New electromagnetic corrections modify neutron beta decay predictions.
• Results have implications for comparing lattice QCD with experiments.
• Beta decay experiments can constrain new physics beyond the Standard Model.