Spin-exchange optical pumping

Ishikawa et detected the free-induction signals of xenon atoms polarized by spin-exchange optical pumping. The temperature dependence of dissolution and spin-polarization transfer of xenon atoms in ethanol is measured by simultaneous detection of both xenon and ethanol protons. 

Spin-exchange optical pumping. Data reported for a number of sites. ... 

T.G. Walker, W. Happer Spin-exchange optical pumping of noble-gas nuclei. Rev. Mod. Phys. 69, 629 (1997)... 

Thus, Duewel et al. [186] have reported the real-time monitoring of styrene polymerization in miniemulsion using a continuous flow of hyperpolarized Xe through the reaction mixture. The hyperpolarization of the Xe via spin-exchange optical pumping allowed the signals to be enhanced and hence the measurements rate and resolution to be increased. 

Appelt S, Baranga AB, Erickson CJ, Romalis MV, Young AR, Happer W. Theory of spin-exchange optical pumping of 3He and Xe. Phys Rev A 1998 58 1412-1439. 

The third basic technique for creating hyperpolarized nuclear spin magnetization makes use of spin exchange optical pumping. This method is commonly applied to hyperpolarize Xe (/= 1/2) in the gas phase. The prineiples of the technique as applied in the MRI eontextwere reviewed reeently by Palaniappan and co-workers, who put partieular emphasis on the CEST approach (called in this case HYPERCEST beeause of combination witb xenon hyperpolarization). Several papers deseribed different teebnique for preparation of byperpolarized Xe for bio-... 

The basic apparatus required for spin-exchange optical pumping is identical to that shown in Fig.17.2. The only... 

Polarization by spin exchange of optically pumped Rb observation of y anisotropy anisotropy of y radiation Rn data taking (P79)... 

Let us first discuss a system which is traditional for optical pumping in the Kastler sense [106, 224, 226], namely an optically oriented alkali atom A (see Fig. 1.1) in a noble gas X buffer surrounding. It is important to take into account the fact that in alkali atoms, owing to hyperfine interaction, nuclear spins are also oriented. However, in a mixture of alkali vapor with a noble gas alkali dimers A2 which are in the 1SJ electronic ground state are always present. There exist two basic collisional mechanisms which lead to orientation transfer from the optically oriented (spin-polarized) atom A to the dimer A2 (a) creation and destruction of molecules in triple collisions A + A + X <—> A2 + X (6) exchange atom-dimer reaction... 

Angular Correlation in Multiphoton Ionization of Atoms, S. J. Smith and G. Leuchs Optical Pumping and Spin Exchange in Gas Cells, R. J. Knize, Z. Hit, and W. Mapper Correlations in Electron-Atom Scattering,... 

The basic and much used methods of xenon optical pumping have been described in a number of articles. Typically, HP xenon is produced using spin exchange from optically polarized rubidium vapor in a low magnetic field. A variety of detailed experiments have characterized the rubidium-xenon spin-exchange process (see ref. 191 and references therein). The Rb-Xe spin-exchange rate can be described by the following rate expression ... 

HP xenon by spin exchange with optically pumped Cs. A 1W diode laser tuned at 894.3 nm was used and produced a xenon polarization of 2.5%. Cs is 10% more efficient at polarizing xenon, so the use of higher output diode lasers may make this approach appealing. 

W Happer, E Miron, S Schaefer, D Schriber, WA van Wijngaarden, X Zeng. Polarization of the nuclear spins of noble-gas atoms by spin exchange with optically pumped aUcali-metal atoms. Phys Rev A 29 3092-3110, 1984. 

Spin-exchange between unlike atoms. Spin-exchange collisions have played an important role in optical pumping experiments for they occur not only between like atoms, but also between atoms A and B of two quite different elements. 

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