ISSN:
1432-0649
Keywords:
PACS: 76.60.-k; 68.35.Md; 32.80.Bx
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
129 Xe with a nuclear polarization far above the thermal equilibrium value (hyperpolarized) is used in NMR studies to increase sensitivity. Gaseous, adsorbed, or dissolved xenon is utilized in physical, chemical, and medical applications. With the aim in mind to study single-crystal surfaces by NMR of adsorbed hyperpolarized 129Xe, three problems have to be solved. The reliable production of 129Xe with highest nuclear polarization possible, the separation of the xenon gas from the necessary quench gas nitrogen without polarization loss, and the dosing/delivery of small amounts of polarized xenon gas to a sample surface. Here we describe an optical pumping setup that regularly produces xenon gas with a 129Xe nuclear polarization of 0.7(±0.07). We show that a freeze–pump–thaw separation of xenon and nitrogen is feasible without a significant loss in xenon polarization. The nitrogen partial pressure can be suppressed by a factor of 400 in a single separation cycle. Dosing is achieved by using the low vapor pressure of a frozen hyperpolarized xenon sample.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s003400050592
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