Monitoring Uranium, Hydrogen, and Lithium and Their Isotopes Using a Compact Laser-Induced Breakdown Spectroscopy (LIBS) Probe and High-Resolution Spectrometer

Abstract

The development of field-deployable instruments to monitor radiological, nuclear, and explosive (RNE) threats is of current interest for a number of assessment needs such as the on-site screening of suspect facilities and nuclear forensics. The presence of uranium and plutonium and radiological materials can be determined through monitoring the elemental emission spectrum using relatively low-resolution spectrometers. In addition, uranium compounds, explosives, and chemicals used in nuclear fuel processing (e.g., tributyl-phosphate) can be identified by applying chemometric analysis to the laser-induced breakdown (LIBS) spectrum recorded by these spectrometers. For nuclear forensic applications, however, isotopes of U and Pu and other elements (e.g., H and Li) must also be determined, requiring higher resolution spectrometers given the small magnitude of the isotope shifts for some of these elements (e.g., 25 pm for U and 13 pm for Pu). High-resolution spectrometers will be preferred for several reasons but these must fit into realistic field-based analysis scenarios. To address the need for field instrumentation, we evaluated a previously developed field-deployable hand-held LIBS interrogation probe combined with two relatively new high-resolution spectrometers (λ/Δλ ~75,000 and ~44,000) that have the potential to meet field-based analysis needs. These spectrometers are significantly smaller and lighter in weight than those previously used for isotopic analysis and one unit can provide simultaneous wide spectral coverage and high resolution in a relatively small package. The LIBS interrogation probe was developed initially for use with low resolution compact spectrometers in a person-portable backpack LIBS instrument. Here we present the results of an evaluation of the LIBS probe combined with a high-resolution spectrometer and demonstrate rapid detection of isotopes of uranium and hydrogen and highly enriched samples of (6)Li and (7)Li.

A critical review of recent progress in analytical laser-induced breakdown spectroscopy

“…aluminium alloy powders) containing rare earth elements in dosed amounts at the time of explosive manufacture [206]. Nuclear threats were also targeted by developing field-deployable instrumentation [207] and isotope-selective data-evaluation methods for lowresolution spectrometers [208].…”

Standoff Detection of Explosives at 1 m using Laser Induced Breakdown Spectroscopy

“…Any application(s), particularly those where the proximity to the sample is limited or restricted because of its hazardous nature, this technique can be one of the important tools in tool-box of analytical techniques. A variety of applications of this technique have been reported in diverse fields of pharmaceuticals 5 , nuclear 6 , biological 7 , explosives 8 , radiological 9 , archeological 10 , and planetary exploration 11 . In recent years, on account of increased threat to the homeland security, the efforts for detection of explosives and its related compounds has seen major thrust in the global community as well as India.…”

Lifetime Analysis of Titanium Neutral and Singly-Ionized Species in LIBS’s Plasmas: A Physical Chemistry Experiment

“…LIBS has many advantages including multi-element detection, little or no sample preparation, analysis of solids, liquids, and gases, real time analyses, and a requirement of only optical access to the surface. [1,2] There are also many applications of LIBS, some of which include metal sorting, heavy metal determination, fissile material detection, geochemical fingerprinting, space exploration, and explosive detection [3][4][5][6][7][8].…”