Optics Of Cosmic Dust I PDF Download

Biological warfare (BW) agents are a prime concern to both military and civilian personnel because of both their lethality and the resulting terror they would inflict upon a population. Dc testing and identifying aerosols is a primary objective of the US DoD and many other institutions worldwide. Light scattering may provide an automated means of rapidly detecting and identifying potentially lethal aerosols real-time without the use of chemical reagents or expensive maintenance. Since organic particles tend to fluoresce, many detector systems have focused on measuring this property to identify potentially harmful particles to raise an alarm. However, because fluorescence signals tend to be weak and smooth, it is difficult to differentiate among species of biological particles. Natural backgrounds vary widely and may cause false alarms. For this reason, other information is needed about the particle system that may be gathered from the elastic scattering spectrum. One property of 3W agents is that when they are aerosolized, they tend to aggregate into clusters. From the scattering signal, it might be possible to characterize the individual spores making up the cluster to help in the identification. However, again it is essential to be aware of the natural background signals caused by dust, diesel fumes, pollen, etc. and to develop methods to distinguish between these particles and the particles of concern.