Measurement of Neutron Polarization and Transmission for the SNS nEDM Experiment.*

The existence and size of a neutron electric dipole moment (nEDM) remains an important question in particle and cosmological physics. The SNS nEDM experiment proposes a new limit for nEDM search by using ultra-cold neutrons (UCN) in a bath of superfluid helium. The experiment uses polarized 8.9{\AA} neutrons to create polarized UCN in situ in superfluid helium via superthermal downscattering. This process requires the 8.9{\AA} neutrons to retain their polarization as they pass through the magnetic shielding and nEDM cryostat windows. This talk will describe a setup to measure the neutron polarization loss from the magnetic shielding and cryostat windows.