Abstract #1295

Saam B, Jacob R, Anger B, Minard K

Hyperpolarized 3He has widespread interest as a signal source for MRI in the lung. Two recent advances in the physics of spin-exchange optical pumping (SEOP) have led to dramatic enhancements in the efficiency of generating hyperpolarized 3He: the use of spectrally narrowed diode-laser arrays and hybrid SEOP, which employs both potassium and rubidium as alkali-metal intermediaries. We have combined these techniques in constructing two polarizers, both a prototype and more fully engineered system. We report up to 50% 3He polarization in 0.5 barL of gas in valved and refillable glass cells, achieved in 4 h.