Development of voltage reading adc devices for magnetometry in the Nab experiment

Neutron beta decay is a fundamental process whose occurrence and outcome can be studied to gain insight into the weak interaction.The products of this can process can be studied to calculate the beta decay correlation λ. The Nab experiment at the SNS in Oak Ridge National Lab will make measurements of the electron neutrino correlation a and the electron energy spectrum b. These measurements will be used to make a precise determination of λ. This value, in tandem with the neutron lifetime τ, can be used to test CKM matrix unitarity. To do this, Nab utilizes a large cryogen-free superconducting magnet spectrometer with complicated magnetic fields and gradients to guide the decay products to two silicon detectors. To accomplish Nab’s goals, the magnetic field at all points in the spectrometer with 0.1% error or less. We will use a high precision Hall probe and high resolution ADC to make precise measurements of the magnetic field in the spectrometer We will present an overview of the work done to prepare these devices for a magnetometry campaign in December 2025.