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Laser-induced migration and isotope separation of epi-thermal monomers and dimers in supercooled free jets

Published online by Cambridge University Press:  07 June 2005

JEFF W. EERKENS
JEFF W. EERKENS
Affiliation:
CRISLA Research Laboratory, Nuclear Science and Engineering Institute, University of Missouri, Columbia, Missouri
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Abstract

Explicit relations are developed to estimate the outflux of migrating isotopomers iQF6 to the outskirts of a supersonic supercooled free jet whose core is irradiated by a co-axial laser beam and intercepted by a skimmer that separates core gas from peripheral gases. The QF6 target gas is diluted in carrier gas G (G = He, N2, Ar, Xe, SF6, etc.) which determines the jet's supersonic characteristics and forms QF6:G dimers at low temperatures. Under isotope-selective laser excitation, excited iQF6* convert their vibrational energy V into kinetic energy T after forming transient iQF6*:G dimers that dissociate in sub-microseconds. Three migrating groups with different transport parameters are created in the jet: thermal monomers, faster-moving epithermal monomers, and slower-moving dimers. Jet-core-fleeing QF6 is enriched in iQF6 due to enhanced outwards migration of iQF6! epithermals and reduced escape of jQF6:G dimers in the jet. Isotope enrichments in the rim gases are highest for heavier carrier gases such as G = Xe or G = SF6.

Keywords

Epithermal moleculesLaser isotope separationMonomer versus dimer migration ratesSF6 and UF6Supersonic free jets

Information

Type
Research Article
Information
Laser and Particle Beams , Volume 23 , Issue 2 , June 2005 , pp. 225 - 253
Copyright
2005 Cambridge University Press

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