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Two-dimensional fluorescence spectroscopy of uranium isotopes in femtosecond laser ablation plumes.

ABSTRACT: We demonstrate measurement of uranium isotopes in femtosecond laser ablation plumes using two-dimensional fluorescence spectroscopy (2DFS). The high-resolution, tunable CW-laser spectroscopy technique clearly distinguishes atomic absorption from ²³⁵U and ²³⁸U in natural and highly enriched uranium metal samples. We present analysis of spectral resolution and analytical performance of 2DFS as a function of ambient pressure. Simultaneous measurement using time-resolved absorption spectroscopy provides information on temporal dynamics of the laser ablation plume and saturation behavior of fluorescence signals. The rapid, non-contact measurement is promising for in-field, standoff measurements of uranium enrichment for nuclear safety and security.

SUBMITTER: Phillips MC

PROVIDER: S-EPMC5476594 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Two-dimensional fluorescence spectroscopy of uranium isotopes in femtosecond laser ablation plumes.

Phillips Mark C MC Brumfield Brian E BE LaHaye Nicole N Harilal Sivanandan S SS Hartig Kyle C KC Jovanovic Igor I

Scientific reports 20170619 1

We demonstrate measurement of uranium isotopes in femtosecond laser ablation plumes using two-dimensional fluorescence spectroscopy (2DFS). The high-resolution, tunable CW-laser spectroscopy technique clearly distinguishes atomic absorption from <sup>235</sup>U and <sup>238</sup>U in natural and highly enriched uranium metal samples. We present analysis of spectral resolution and analytical performance of 2DFS as a function of ambient pressure. Simultaneous measurement using time-resolved absorp ...[more]

PMID: 28630409

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