Magnetic characterization of the rotation system for the ARIADNE axion experiment

The Axion Resonant Interaction Detection Experiment (ARIADNE) will look for spin-dependent interactions mediated by the QCD axion field in the mass range of 1μeV to 6meV. Modulating an unpolarized Tungsten mass in close proximity to polarized helium-3 gas creates an effective transverse magnetic field as seen by the He-3 spins, which drives a nuclear magnetic resonance transition. The experiment relies on low magnetic gradients for the helium to remain polarized during transport to the sample cell, limiting ordinary magnetic noise with superconducting magnetic shielding as well as a stable rotary system to modulate the axion-signal from the source mass. The latest results on magnetic characterization of the motor used to rotate the source mass will be discussed.