Weak Decay of Magnetized Pions

Area of Science:

• Particle Physics
• Quantum Field Theory
• Lattice QCD

Background:

• Charged pion leptonic decay is a fundamental process in particle physics.
• Background magnetic fields can break Lorentz symmetry, altering particle decay properties.
• Previous studies have not fully explored pion decay in strong magnetic fields.

Purpose of the Study:

• To investigate the impact of background magnetic fields on charged pion leptonic decay.
• To introduce and calculate new decay constants arising from Lorentz symmetry breaking.
• To determine the magnetic field dependence of pion decay rates.

Main Methods:

• Nonperturbative lattice QCD calculations using Wilson and staggered quarks.
• Extrapolation of results to the continuum limit.
• Calculation of electroweak amplitudes for the full decay rate.

Main Results:

• A new fundamental decay constant is introduced and calculated.
• The magnetic field dependence of both usual and new decay constants is determined.
• The muonic decay rate of charged pions is found to be drastically enhanced by magnetic fields.

Conclusions:

• Background magnetic fields significantly alter charged pion leptonic decay.
• The enhancement of muonic decay has potential astrophysical implications.
• Lattice QCD provides a robust framework for studying particle physics in extreme conditions.