Numerical Optimization Methods for Maximizing Field Uniformity for a Ramsey Based nEDM Measurement

To account for the matter-antimatter asymmetry observed in the universe, it is necessary to propose new sources of CP symmetry violation beyond those permitted by the Standard Model. Extensions predict a neutron electric dipole moment (nEDM) significantly larger than the Standard Model (2x10⁻³²e·cm). At Los Alamos National Laboratory (LANL), we aim to measure the nEDM with a statistical uncertainty of ~2x10⁻²⁷e·cm using the separated oscillating field (Ramsey) method with ultracold neutrons. Achieving this sensitivity requires exceptional uniformity of the applied magnetic field. The experiment is conducted within comprehensive shielding: passive shielding using μ-metal and active shielding provided by a large coil system encasing the setup. To optimize magnetic field homogeneity and suppress environmental perturbations, COMSOL Multiphysics is used to numerically determine optimal current distributions for the active shielding coils. Through systematic simulations across various scenarios, these optimization tools yield practical solutions for minimizing the influence of external magnetic fields—improving field uniformity for precise nEDM measurements.