@article{bibcite_36857,
  author = {Londrea J Garrett and Igor Jovanovic and George C.-Y Chan},
  title = {Spectral emission characteristics near 646~nm and plasma properties of laser-induced plasma of gaseous uranium hexafluoride},
  abstract = {<p>We present a detailed investigation of the temporal evolution of line and continuum emissions in laser-induced breakdown spectroscopy (LIBS) of gaseous uranium hexafluoride (UF<sub>6</sub>), focusing on the spectral region near 646\&nbsp;nm. Spectral emission features, signal-to-background ratios (SBRs) of selected uranium lines, and spectral linewidths were examined under varying UF<sub>6</sub> pressures (15{\textendash}60\&nbsp;Torr) and laser pulse energies (10{\textendash}60\&nbsp;mJ). Higher pressures and pulse energies enhanced continuum emission and reduced SBRs but did not cause significant spectral congestion. Additional studies with the use of different laser systems, including nanosecond-pulsed Nd:YAG lasers (at fundamental and various harmonics) and a femtosecond-pulsed Ti:sapphire laser, revealed long-lived plasma continua in all cases. This persistent continuum is attributed to a pseudo-continuum from overlapping molecular emissions, as its intensity scales linearly with electron number density, deviating from the expected quadratic dependence of classical ion{\textendash}electron interactions for free-free and free-bound continuum emission. Based on plasma persistence time, SBR, U II/U I intensity ratios, and electronic excitation temperature, no fundamental advantage was found for femtosecond-pulsed lasers over conventional nanosecond-pulsed ones for UF<sub>6</sub> enrichment assay with direct LIBS measurement.</p>},
  year = {2026},
  booktitle = {Spectrochimica Acta Part B: Atomic Spectroscopy},
  journal = {Spectrochimica Acta Part B: Atomic Spectroscopy},
  series = {Spectrochimica Acta Part B: Atomic Spectroscopy},
  volume = {236},
  pages = {107357},
  month = {02/2026},
  institution = {Elsevier BV},
  publisher = {Elsevier BV},
  issn = {0584-8547},
  url = {https://doi.org/10.1016/j.sab.2025.107357},
  doi = {10.1016/j.sab.2025.107357},
}