Tomáš Gavenda, Vojtech Kresalek, Tomas Bata
The research performed by authors of this article in the year 2013  lead to the following presented research. Different samples of commercially known kinds of gunpowder prepared by various manufactures were measured to obtain presented data. The article published in 2013  proved, that particular samples can be distinguished from each other using terahertz time-domain spectroscopy. This article presents results of measuring and analysing of gunpowder samples using other methods based on terahertz radiation. Ten different samples of gunpowder were measured during the research. Most of them were based on nitrocellulose, but components of each sample differ. Systems TPS Spectra 3000 by TeraView Ltd. and Tera OSCAT by Menlo GmbH. were used for measurements. Several terahertz radiation based methods were used for researching the possibility of distinguishing different kinds of gunpowder, such as terahertz imaging (using both transitive and reflective imaging method), ATR spectroscopy and reflective variant of time-domain spectroscopy. Frequency ranges differ in dependence on used method, but the range from 0.5 THz to 2.0 THz was measured mostly. Presented research also contains results of measurements of gunpowder compounds, for example compounds with polymer materials (like polyethylene). These measurements are important because of the need for development of new possibilities to detect and identify dangerous materials at airports or other public places. Main contribution of this research is extension of knowledge in the domain of detection, identification and distinguishing of different kinds of gunpowder, which are commercially available and therefore exploitable as dangerous explosive materials. This article, together with the previous presented and already published article , makes comprehensive result of gunpowder properties measurement using methods based on terahertz radiation.  Gavenda T., Kresalek V., “Terahertz time-domain spectroscopy for distinguishing different kinds of gunpowder,” Proc. SPIE 8900, 6 pages (2013).
This study was performed using TeraView's TPS spectra 3000 system. (TeraView, Cambridge, UK)