Optically Pumped Magnetometry Strategy for the Los Alamos National Laboratory Neutron Electron Dipole Moment Experiment

The Los Alamos Neutron Electric Dipole Moment Experiment (LANL nEDM) aims to measure the neutron EDM with a statistical uncertainty of 2x10^-27 e-cm in a year-equivalent of data collection using Ramsey's method of separated oscillatory fields. To achieve this, the magnetic field the ultracold neutrons (UCN) experience during their free precession must be known to high precision. The magnetometry strategy for LANL nEDM experiment includes having a double-cell configuration with a Hg comagnetometer, strict magnetic impurity requirements for all materials used in the experiment, and an array of optically pumped magnetometers (OPMs) located outside of the precession volume. This talk outlines the near-term strategy for magnetic field monitoring with a small number of irregularly spaced OPMs. In particular, the ability of the OPM array to identify the appearance of spontaneous magnetization will be reported.