Characterization of Radiation Induced Color Centers in Lithium Fluoride

Interactions between energetic particles and a crystal's lattice structure can lead to observable vacancies in the crystal. In some materials, these vacancies are optically active (aka color centers), thus allowing one to determine the type and trajectory of particles that damage the crystal by fluorescence measurements. Lithium fluoride (LiF) is a particularly good candidate as a passive particle detector due to the relatively light masses of the Li and F ions, allowing for more energetic recoil tracks to be created within the crystal from particle interactions. We have studied the bulk fluorescence of LiF after irradiation by neutrons and gamma rays by characterizing the time and temperature dependence of the fluorescence. These studies are useful in understanding how the history of LiF impacts its fluorescence. Using Light-Sheet Fluorescence Microscopy (LFSM), we also imaged single-site vacancies and damage tracks in 3 dimensions to study single particle interactions.