UC Berkeley

Femtosecond and faster lasers have opened a new regime of physics. Because their pulseduration is shorter than the phonon relaxation time of most materials, they deposit energy with almost no loss to the surrounding area. Calibration curves using NIST Glass, CRM 125-A, and tungsten metal allowed the use of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LAMS) to interrogate element distributions in Pressurized Water Reactor fuel surrogates fabricated at Los Alamos National Laboratory. LAMS can be faster and less expensive than traditional acid dissolution of surrogate PWR fuel pellets. With traditional acid dissolution, spatial information is mostly lost, whereas LAMS oers the possibility of three-dimensional isotope analysis. This three-dimensional data could help resolve longstanding issues in ssion product movement through the fuel. The LAMS system used here had a limit of detection for tungsten of approximately 800 parts per billion, which is better than the Los Alamos neutron tomography study (Tremsin et al., 2013) but not state of the art. A calibration curve for tungsten was obtained with a least-squares residual R2 = 1 (Sewall, 1921). Isotope ratios were generally within 1% of declared values. These results corroborate the ndings of LANL neutron tomography study and suggest LAMS to be a cost eective approach to the rapid three-dimensional analysis of spent fuel. Other applications may include fuel fabrication, additive manufacturing, and nuclear forensics.