Fabrication and Testing of Spin Transport Coils for the nEDM@SNS ExperimentBreanna Hess, Andrew Mullins, Cory Smith, Christopher CrawfordCollege of Arts and Sciences, University of Kentucky*

A neutron electric dipole moment (nEDM) violates CP symmetry, one of the Sakharov conditions required to explain the observed baryon asymmetry in the universe. In order to improve on the current upper limit on the nEDM of 1.8 x 10^-26 e cm, next generation experiments will need an extremely uniform precession field and a highly polarized comagnetometer, such as the He-3 comagnetometer of the nEDM@SNS experiment, polarized in an atomic beam source (ABS). Prototype coils were fabricated to taper the holding field from a few Gauss in the vicinity of the ABS down to 30 mG along the 1 m flight path of the He-3 atoms. They were constructed by gluing wires to a plastic mesh according to a printed pattern underneath the mesh. The measured field map was used in spin transport codes to calculate the polarization efficiency.