Autori: M. Iovea, G. Mateiasi, O.G. Duliu, M. Neagu, M. Mangu

Editorial: Materials Evaluation, vol 67, No.12, p.1343-1349, 2009.

Rezumat:

The techniques of dual-energy X-ray Radioscopy (DR) and Computed Tomography (CT) for baggage threat detection have been substantially improved during the years after the 9/11 attack and the series of terrorist attacks in Europe. Almost all airports worldwide are nowadays routinely using dual-energy baggage screeners (DR) as first-level threat detection equipment. The largest ones have also already installed dual-energy CT or Multi-view systems in order to achieve the high level of confidence requested for screening. The new hand-held baggage scanners are also faster, have improved image resolution and are capable of discriminating at least between organic, inorganic or metallic materials.
Some of these equipments implement also algorithms for automated threat identification but, presumably due to still poor performance, the manufacturers are not specifying the accuracy their equipment achieves in the measurement of the Effective Atomic Number (Zeff) and Density (ρ) of the scanned baggage. A high accuracy level is nevertheless critical for the present day dual-energy screeners, since the final identification decision still depends in large measure on the operator skills. In addition, although the existent CT systems are capable of automatic measurements of both the Zeff and Density, they are very large, expensive, offer a relatively small throughput, and still could produce a small false positive alarm rate.

Cuvinte cheie: X-Ray, radioscopy, dual-energy, explosives, atomic effective number