Uranium Characterization by Shaped Femtosecond Laser-induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) is a well-establishedtechnique for elemental analysis of materials. There isgrowing interest in using LIBS for nuclear forensics applicationsbecause of its fast in situ capability and minimum or no requirementsfor sample preparation. Hence, new methods to improvethe LIBS sensitivity continue to be explored. Controlling theshape of ultrafast laser pulses that produce and interact with theplasma can be used to improve LIBS signals, and can be accomplishedby the use of Fourier-domain pulse shapers. We presentthe result of our initial studies of natural uranium metal usingLIBS with shaped femtosecond pulses. The acquired spectraare analyzed to determine the systematic effects of various pulseshapes on uranium spectral lines. The objective of our study isto determine the strategies for feedback-driven optimization ofpulse shape for improvement of LIBS sensitivity in studying uraniumfor nuclear forensics applications.