Recent advances in spin-exchange pumped polarized 3He target technology

We have produced long lifetime 3He spin-exchange cells from Corning 7056 glass. The lifetimes of single cells have approached the 3He3He bulk-limited lifetime (250 h at a density of 8 × 1019 cm−3, (3 amagats)). Corning 7056 glass has the advantage of being a much easier glass for the glassblower to work, allowing for more complex cell designs. In our experiments at Michigan and at SLAC, we have implemented laser diode arrays for spin-exchange optical pumping. In particular, for experiment E154 at SLAC, we achieved high polarizations in high-density 3He targets using laser diode arrays.