10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Elastic and Inelastic Scattering of Laser-Trapped Particles: Optically Characterizing Trace Aerosols
PATRICIO PIEDRA, Aimable Kalume, Yong-Le Pan, Gorden Videen, U.S. Army Research Laboratory
Abstract Number: 595 Working Group: Aerosol Physics
Abstract Optical detection of chemical and/or biological agents is a significant challenge since these particles can be present in the atmosphere in trace amounts. Optical detection of these agents requires exquisite accuracy to isolate the optical signal of a few particles in a background of numerous air molecules, other aerosol particles, and atmospheric compounds. Single particle laser-trapping is a technique pioneered at the U.S. Army Research Laboratory that allows us to capture a particle in the air for a prolonged time and collect very detailed information of the particle’s elastic (i.e., Rayleigh, Mie scattering) and inelastic (i.e., Raman and fluorescent scattering) optical signal. In this study, we measure elastic and inelastic light scattering signal of several laser-trapped aerosol particles. Our measurements are analyzed, and multi-dimensional statistical clustering techniques are applied to mathematically group particles by their optical similarities in both elastic and inelastic scattering parameters. These clustering techniques are expected to yield significant differences between distinct types of aerosol particles. In future work, we expect to apply deep learning techniques to identify trace amounts of aerosols using data collected in our experiments. If this preliminary proof of concept is successful, it has the potential to lead to innovative studies aiming to improve remote sensing techniques of trace chemical and/or biological agents.