Simulation of Charged Particle Trajectories in the Neutron Decay Correlation Experiment abBA

Area of Science:

• Nuclear physics
• Particle physics
• Experimental physics

Background:

• Neutron decay is a fundamental process in nuclear physics.
• Precise measurements of neutron decay observables are crucial for testing the Standard Model.
• Previous experiments faced challenges with systematic effects impacting measurement accuracy.

Purpose of the Study:

• To propose and simulate the abBA experiment for direct detection of neutron decay products.
• To assess the impact of systematic effects on experimental observables.
• To validate simulation methods for particle trajectory analysis.

Main Methods:

• Detailed simulations of proton and electron trajectories within spatially varying electric and magnetic fields.
• Utilizing commercial (Simion) and custom software for orbit tracking.
• Employing analytical tools based on adiabatic invariants for transport calculations.

Main Results:

• The proposed abBA spectrometer geometry demonstrates substantial immunity to most systematic effects.
• Simulations accurately predict particle trajectories, including low-energy proton reversals.
• Transport calculations using adiabatic invariants show good agreement with full equations of motion.

Conclusions:

• The abBA experiment's design is well-suited for precise neutron decay measurements.
• The simulation approach validates the experimental design and its robustness.
• The findings support the feasibility of achieving high-accuracy measurements of neutron decay correlations.