Non-invasive inspection of baggage using coherent X-ray scattering

The requirement for equipment to detect with a high degree of specificity (low false positive rate) explosive materials in passenger baggage is an obvious one. X-ray equipments commercially available at present include dual energy transmission imagers and computer aided tomography (CAT) scanners. These essentially yield effective atomic number and density information in 2D and 3D respectively. Both technologies provide highly capable and practical equipment for screening bags and are improving all the time in terms of the precision with which the effective atomic number and density may be determined. They do, however, remain inherently chemically nonspecific. In this paper, we report work carried out to evaluate X-ray coherent scattering. The aim is to achieve the excellent chemical specificity of NQR, allied with the penetration of X-ray and nuclear methods.