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Optically Polarized He3



Thomas R. Gentile, P.J. Nacher, B Saam, T G. Walker


This article reviews the physics and technology of producing large quantities fo highly spin- polarized, or hyderpolarized, He3 nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping, and surveys applications of polarized He3. Several recent developments are emphasized for each method. for SEOP, the use of spectral narrowed lasers and Rb/K mixtures has substantially increased the achievable polarization and polarizing rate. MEOP in high magnetic fields has like-wise significantly increased the pressure at which this method can e performed, and has led to the observation of a light-induced relaxation mechanism. In both methods the increased capabilities have led to more extensive study and modeling of the basic underlying physics. New unexplained dependence of relaxation on temperature and magnetic filed have been discovered in SEOP cells. Applications of both methods are also reviewed, including targets for charged particle and photon beams, neutron spin filters, magnetic resonance imaging, and precision measurements
Reviews of Modern Physics


He3, hyperpolarized, spin-polarized
Created December 1, 2017, Updated November 10, 2018