Proceedings Article | 3 June 2011
Proc. SPIE. 8018, Chemical, Biological, Radiological, Nuclear, and Explosives (CBRNE) Sensing XII
KEYWORDS: Luminescence, Atmospheric particles, Particles, Clouds, Aerosols, Atmospheric modeling, LIDAR, Atrial fibrillation, Aerodynamics, Backscatter
Light detection and ranging (LIDAR) systems have demonstrated some capability to meet the needs of a fastresponse
standoff biological detection method for simulants in open air conditions. These systems are designed
to exploit various cloud signatures, such as differential elastic backscatter, fluorescence, and depolarization in
order to detect biological warfare agents (BWAs). However, because the release of BWAs in open air is forbidden,
methods must be developed to predict candidate system performance against real agents. In support of such
efforts, the Johns Hopkins University Applied Physics Lab (JHU/APL) has developed a modeling approach to
predict the optical properties of agent materials from relatively simple, Biosafety Level 3-compatible bench top
measurements. JHU/APL has fielded new ground truth instruments (in addition to standard particle sizers, such
as the Aerodynamic particle sizer (APS) or GRIMM aerosol monitor (GRIMM)) to more thoroughly characterize
the simulant aerosols released in recent field tests at Dugway Proving Ground (DPG). These instruments include
the Scanning Mobility Particle Sizer (SMPS), the Ultraviolet Aerodynamic Particle Sizer (UVAPS), and the
Aspect Aerosol Size and Shape Analyser (Aspect). The SMPS was employed as a means of measuring smallparticle
concentrations for more accurate Mie scattering simulations; the UVAPS, which measures size-resolved
fluorescence intensity, was employed as a path toward fluorescence cross section modeling; and the Aspect, which
measures particle shape, was employed as a path towards depolarization modeling.
