LASER-INDUCED ISOTOPE SEPARATION OF SF 6 AND UF 6

D. FREGENAL; E. CORTIZO; P. FAINSTEIN; S. ENCINA; J. D. FUHR; E. KAUL; P. KNOBLAUCH; A. LAMAGNA; P. MACEIRA; M. ZARCO; J. FIOL

Rosario

Workshop; Atomic collisions and applications 2019 Workshop in honor of Prof. Roberto D. Rivarola; 2019

Instituto de Física, Universidad Nacional de Rosario

Laser-assisted isotope separation technologies have shown great prospect for several elements due to their high efficiency and selectivity. In particular, one version of these techniques, Molecule Laser Isotope Separation technique, MLIS, is based on laser selective excitation of roto-vibrational modes of molecules in a supercooled beam. The cooling, which narrows the radiation absorption lines, is produced by supersonic expansion through a nozzle. Even though this method avoids  solidification of the molecules naturally occurring at these temperatures, clusters of relatively small number of molecules are formed. Either selective repression of cluster formation, or cluster fragmentation induced by selective excitation, are the main mechanisms behind the investigated method for isotope separation.In this work we present results of experiments on selective excitation and MLIS for UF6 and SF6. Pulsed free expansions of diluted mixtures of these molecules with noble gases were irradiated by pulsed lasers tuned for excitation of the ν 3 vibration mode of the molecule. Final products of the beam selected by a skimmer were analyzed using time of flight spectrometry. We describe the experimental setup and some particular characteristics related to the synchronization of the molecular beam pulse and two pulsed lasers with different time-scales. We analyze the dependence of the relevant parameters of the experiment on the observed selectivity. We investigated the effect of the molecular beam conditions and irradiation configuration, as well as some of the post-irradiation processes. In particular, we studied the effect of the lapsed time between excitation and diagnostic measurements which spreads the irradiated beam affecting the observed selectivity. Finally, values of isotope selectivity were estimated in each case and its application for isotope separation is discussed.