POLARIZED 3He: FROM WEAK SYMMETRIES TO LUNG IMAGES. Gordon L. Jones. Building 235, Room. A-159, NIST, Gaithersburg, MD 20899(301- 975-6222, email:gordon.jones@nist.gov)

We are developing systems to polarize 3He through both spin-exchange and metastability exchange optical pumping. The first goal for the polarized gas is to make a neutron spin filter. Compared to current neutron polarizers, such a filter would work over a broader energy spectrum and would contribute smaller divergence and gamma backgrounds. A polarizer based on 3He would be useful for fundamental symmetry tests of the electro-weak interaction as well as materials science studies of magnetic properties. We now have the ability to make cells with long relaxation times that are appropriate for spin filter tests. The ability to polarize 3He also provides a way to image air spaces in the body using magnetic resonance imaging (MRI). It is difficult to get high resolution images of human lungs using current medical technology. We have a preliminary lung image obtained with polarized 3He.