Design of an Integrated Inspection System For Detection of Explosive and Illicit Materials

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1 Design of an Integrated Inspection System For Detection of Explosive and Illicit Materials IAEA 2 nd CRP Meeting, Mumbai, November 2007 R. M. Megahid Nuclear Research Centre, Atomic Energy Authority Cairo, Egypt E Mail: rmegahid 2573@hotmail.com

2 Background and Justification The use of reliable techniques at all ports of entry ; sea, land and air has became realistic after the tragic events of September It has become even more realistic since the attacks in London subway of July 2005 and the the attacks on hotels and shopping centre of Sharm El-Sheikh city, Egypt of October 2004 and July Since then, the possibility of further attacks against civil populations is one of the most important issues on the international agenda. Therefore, illicit trafficking of explosives and radioactive, mainly fissile materials through the conventional commercial networks became a real challenge to security of future.

3 X-ray Based Cargo Inspection Systems X-ray based systems are most common form of non-invasive technology in use X-rays detect differences in material density and produce image of vehicle and cargo contents Contraband detection actually occurs by visual inspection of image and or use of sophisticated software Brian Lewis,.Port, Security; Container Inspection Technology., 2002 Technical Report, Logistics Institute, Georgia Tech & National University of Singapore

4 Contraband Detection the density of a plantain appears exactly the same as that of cocaine molded and painted to look like a plantain when both are put through an X-rayX ray When cargo and contraband are of similar densities, contraband detection is very difficult X-ray image will be cluttered and visually complex Contraband could be hidden behind dense cargo Other advanced imaging techniques are required Seeking Safe Harbor. Government Executive Magazine, 1 March 2002

5 TC-SCAN FMG/RMG Fixed with Moving Gantry Source: γ-ray 300Ci Scan Meth. Gantry moves on rails fixed on the ground. Throughout : > 30con/h Target dim. Max 2.9m(h)x3m(w)

6 Why Neutrons? Neutron techniques are uniquely suited to be the core of inspection systems. They have the essential capabilities required to do the job, including high penetrability, specificity, and speed. They are inherently non intrusive, and the data they generate is amenable to advanced data analysis techniques and automatic decision making. Neutrons are the most effective nuclear radiation to achieve the above mentioned requirements especially where material specificity is required.

7 Attinuation Coefficints for Neutrns and X-rays

8 γ-ray transitions of relevant elements (MeV) Element capture inelastic H 2.2 none C N ,2.3, 5.1 O , 6.1 Cl 6.11,

9 Gamma rays produced by irradiating the object by neutrons, gives the elemental composition of the material. Knowing the nuclear cross sections and estimating the absorption factors of different materials, make it possible to perform qualitative and quantitative analysis of elements of the object even in depth. Furthermore, with the use of Tagged neutrons it is possible to determine the local distribution of elements inside the object volume that has been identified as suspect. Secondary neutrons produced by the irradiation of the object can be used with spectral analysis to identify the presence of fissile materials in the inspected volume.

10 INSPECTION BY FAST NEUTRONS Possesses the following Features: Good penetration, Multiple elemental signature, Lowest cost among fast neutron Interrogation, Uses neutrons from neutron generators, India meeting.lnk Applicable to loaded vehicles and containers, Provides Imaging by PFNA (nanosecond Pulsed Fast Neutron Analysis) and Associated Particle), Gives clean elemental signals and a good spatial resolution. This makes the technique a most unique and powerful tool for cargo inspection.

11 Objectives of Project To develop and adopt nuclear techniques based on applying small neutron sources and neutron generator in combination of conventional methods with gamma source. These techniques will be used to detect bulk (more than 1 Kg) explosives and illicit materials to strength measures that enhance the safety and security of transportation.

12 Detailed work plan Design of source shield and moderator with beam collimators for radioisotope and neutron generator neutron sources. Design of source shield with beam collimators for 60Co gamma source. Design of shield and collimators for neutron/ gamma detector. Design of gamma shield for detectors of gamma spectrometer.

13 Design a cask to transport the fissile material ( one of the stored fuel bundle of ETRR-1 1 reactor) to the container simulator. Installation and calibration the gamma- spectrometer with inorganic scintillator and HPGe detectors. Performing measurements for inspection with radioisotope neutron sources. Performing measurements for inspection with 60Co source. Performing computational and modeling to optimize source and detector parameters to suit different geometries.

14 Project Achievements Design and construction of neutron source shield and collimators. Design and construction of gamma source shield and collimators. Design and construction of neutron/ gamma detector shiel and collimators. Design and construction of shield for inorganic scintillators. Installation and calibration of gamma spectrometer with NaI(Tl) ) detector. Calibration of neutron/gamma spectrometer.

15 Measurement of gamma-ray spectra resulting from explosive material interrogated by neutrons from 252 Cf neutron source. Measurement of fast neutron spectra resulting from explosive material interrogated with neutrons from 252 Cf neutron source.

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28 5 Neutron flux, neutrons.cm -2.s -1.MeV a Neu tron en erg y, MeV Fast neutron s pectrum from 252 Cf neutron source transm itted through landmine at 45 degree.

29 Gamma flux, photons.cm -2.s H C N O Fe Gamma energy, MeV Spectrum of gamma rays measured by organic scintillator at 135 degree (transmitted beam) from explosive materiasl.

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37 Work Plan for future 1. Use the installed Inspection system to search for objects hidden inside different benign materials. 2. Inspection will be performed by scanning the container using the radiography system. 3. Identifying the suspect object by Fast/Thermal neutron Elemental analysis. Using Neutrons emitted from pulsed neutron generator and neutrons from Pu-α-Be source. The gamma ray spectra will be measured using

38 Conclusions Nuclear based technique offer unique capabilities for inspection of both small and large objects for explosives nuclear materials, drugs, narcotics, and other illicit substances. These Techniques span the range from being single element specific, with emission tomography type imaging (TNA), to multiple element and fully direct imaging with time of flight (PFNA). The Presented and discussed nuclear techniques can be applied for a broad range of applications. Few of these techniques have been implemented, others need modification development, to adapt various applications.

39 Use has to be made of the facilities, experience gained by Egyptian team engaged in national project for landmine detection and identification by nuclear techniques. A national project must be initiated based on the nuclear facilities and human resources of the Egyptian Atomic Energy Authority to develop and adopt inspection advanced technologies for different security aspects.