Diffusive Transfer of Polarized 3He Gas through Depolarizing Magnetic Gradients

James D. Maxwell; Charles S. Epstein; Richard G. Milner

doi:10.1016/j.nima.2015.01.004

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arXiv · 1412.6167

Diffusive Transfer of Polarized 3He Gas through Depolarizing Magnetic Gradients

James D. Maxwell·Charles S. Epstein·Richard G. Milner

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Abstract

Transfer of polarized 3He gas across spatially varying magnetic fields will facilitate a new source of polarized 3He ions for particle accelerators. In this context, depolarization of atoms as they pass through regions of significant transverse field gradients is a major concern. To understand these depolarization effects, we have built a system consisting of a Helmholtz coil pair and a solenoid, both with central magnetic fields of order 30 gauss. The atoms are polarized via metastability exchange optical pumping in the Helmholtz coil and are in diffusive contact via a glass tube with a second test cell in the solenoid. We have carried out measurements of the spin relaxation during transfer of polarization in 3He at 1 torr by diffusion. We explore the use of measurements of the loss of polarization taken in one cell to infer the polarization in the other cell.

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James D. Maxwell, Charles S. Epstein, Richard G. Milner. 2014-12-18. Diffusive Transfer of Polarized 3He Gas through Depolarizing Magnetic Gradients. https://doi.org/10.1016/j.nima.2015.01.004

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