Uranium Oxide Emission from Laser-Produced Plasma

The formation and emission of molecular species in a laser-produced plasma have been the subject of a number of recent studies. In laser-induced plasmas molecules are formed through a number of reaction pathways: combustion (oxidation) by direct interaction with the ambient atmosphere, recombination between species present within the plasma, and fragmentation of larger molecular clusters. However, even though extensive studies are available in the literature, still there exists a lack of knowledge about when and where the molecules are formed in a transient plasma system like a LPP. Typically, the molecular emissions are observed when the plasma has cooled and undergone significant expansion into the ambient atmosphere, and molecular emission persist for longer periods compared to the excited atomic and ionic emissions. Recent studies have shown that shock waves formed during LPP expansion hinder molecular formation through combustion at early times of its evolution.1 The emission intensity, delay, and persistence of the atomic, ionic, and molecular emissions are influenced by the plasma chemistry.