A preliminary investigation is made into the possibility of applying the passive standoff detection technique to the identification of radiological and related products. This work is based on laboratory measurements of the diffuse reflectance from a number of products, including U<sub>3</sub>O<sub>8</sub> , CsI, SrO, I<sub>2</sub>O<sub>5</sub> , and La<sub>2</sub>O<sub>3</sub>. These reflectances are incorporated into the MODTRAN4 radiative-transfer model to simulate the nadir radiance from surfaces consisting of these radiological or related materials. The simulations are performed for two situations: at an altitude of 1 m above the ground, to simulate the passive detection of nuclear products with a hand-held instrument, and at an altitude of 1 km, to simulate a passive sensor carried aboard an aircraft. The results of the simulations under idealized conditions, as well as the results of one measurement, show that the passive standoff detection of radiological products by Fourier-transform infrared radiometry may be possible.
© 2004 Optical Society of America
(030.5630) Coherence and statistical optics : Radiometry
(120.0280) Instrumentation, measurement, and metrology : Remote sensing and sensors
(280.1120) Remote sensing and sensors : Air pollution monitoring
(300.6340) Spectroscopy : Spectroscopy, infrared
Eldon Puckrin and Jean-Marc Thériault, "Passive standoff detection of radiological products by Fourier-transform infrared radiometry," Opt. Lett. 29, 1375-1377 (2004)