Laser-polarized liquid xenon

We present the first liquid-phase studies of hyperpolarized Xe, Xe in which the polarization of 129Xe is much greater than thermal. Using grams of Xe of natural isotopic composition with 6% polarization of the 129Xe, we examined the lifetime of the 129Xe polarization in the liquid as a function of field and temperature. Our measurements showed that surface effects make a significant contribution to the relaxation rate. Lifetimes in excess of 30 min were observed. The long lifetimes and high polarization present several new applications for liquid Xe.