|Abstract:||Spectroscopy in its many utilities presents the ability to remotely sense species present in potentially hazardous conditions. Of recent interest is the development of technologies to detect the presence of actinide materials, a group of radioactive species typically used in the manufacture of nuclear devices. Current spectral databases are incomplete with regard to less-studied materials, such as the actinide group. In order to assist in the development of this technology, the spectral signatures of these materials need to be found and catalogued.
Laser-induced breakdown spectroscopy (LIBS) is a commonly-used method to observe the spectra of materials in plasma conditions. This technique was used in conjunction with absorption spectroscopy, which provides the ability to determine concentration. Tests were performed on two samples, a pure Uranium sample, and an alloy of U3¬Si2, in order to determine changes in spectral signatures when ablated in various environments of different composition and pressure. The Uranium sample was first tested in varying concentrations of O2, N2, and Ar to observe changes in U I and U II species signatures. It was then tested targeting the UO transition at 593.55 nm to observe trends with ambient O2 concentration, pressure, laser power, and spatial location in plasma. The U3Si2 sample was tested to observe and compare temporal changes in U I, U II, Si I, UO, and SiO species signatures.