A METHOD AND APPARATUS FOR DETECTION OF RADIOACTIVE MATERIALS

• US 20070001123A1
• Filed: 07/06/2005
• Published: 01/04/2007
• Est. Priority Date: 10/18/2004
• Status: Abandoned Application

• Current Assignee: Bubble Technology Industries Inc.
• Original Assignee: Bubble Technology Industries Inc.
• Inventors: Ing, Harry, Li, Liqian, Koslowsky, Vernon, Chow, Jimmy, Gao, Hui, Andrews, Hugh, Clifford, Edward, Locklin, Darren, Ing, Lianne, Tennant, Donald
• Application Number:
  US11/160,729
• Publication Number:
  US 20070001123A1
• Time in Patent Office: Days
• US Class Current: 250/394
• CPC Class Codes: G01T 1/361 with a combination of detectors of different types, e.g. anti-Compton spectrometers intensity measurement with a combination of detectors G01T1/1603; with coincidence circuit G01T1/172; se provisionally also G01T1/36
• CPC Class Codes: G01T 3/001 Spectrometry
• CPC Class Codes: G01V 5/26 Passive interrogation, i.e. by measuring radiation emitted by objects or goods
• CPC Class Codes: G01V 5/281 detecting special nuclear material [SNM], e.g. Uranium-235, Uranium-233 or Plutonium-239

Abstract

In the present invention there is a provided an array of radiation detectors comprising at least one detector capable of detecting both low and high energy gamma radiation and adapted to provide spectrometric identification of the gamma source; at least one detector capable of detecting and providing spectrometric identification of fast neutrons and low resolution gamma spectra; at least one detector adapted to detect thermal neutrons; and, at least one plastic scintillator to give enhanced gamma ray sensitivity.

Claims

1. An array of radiation detectors comprising:

at least one detector capable of detecting both low and high energy gamma radiation and adapted to provide spectrometric identification of the gamma source;

at least one detector capable of detecting and providing spectrometric identification of fast neutrons and low resolution gamma spectra;

at least one detector adapted to detect thermal neutrons; and

,

at least one plastic scintillator to give enhanced gamma ray sensitivity.

2. The array of claim 1, wherein the detector of i) is selected from at least one low energy photon detector sensitive to low energy gamma radiation for suppressing competing background from high energy radiation or included with at least one Nal (Tl) detector.

3. The array of claim 1, further including additional high resolution detectors selected to enhance radioactive isotope identification.

4. The array of claim 1, wherein said array is incorporated in a panel, said panel having processing means.

5. The array of claim 1, further including means for wireless data transmission.

6. The array of claim 1, further including means for data fusion techniques.

7. The array of claim 1, wherein i) comprises sodium iodide activated by thallium (Nal(Tl)) detectors.

8. The array of claim 2, wherein said low energy photon detector comprises Nal (Tl) (activated by thallium) scintillator backed by Csl (Na) scintillator.

9. The array of claim 1, wherein iii) comprises liquid scintillation fast neutron detectors with a volume of the order of 5 inch diameter×

24 inch long.

10. The array of claim 1, wherein the spatial arrangement of i) to iv) is designed to distribute sensitivity uniformly over the detecting surface.

11. The array of claim 1, wherein said array is adapted to be controlled from a remote location.

12. The array of claim 4, wherein each panel includes processing means for calibrating and correcting raw data from each of (i) to (iv) to yield an output.

13. The array of claim 4, wherein the panel comprises part of a system having a plurality of panels.

14. The array of claim 13, wherein said plurality of panels are configured to form a portal monitor for one of pedestrians, parcels, vehicles, containers or rail cargo.

15. The array of claim 14, further including a power source and an indicator device.

16. The array of claim 15, wherein said portal monitor unit is remotely controlled.

18. The portal monitor of claim 17, wherein said shielding baffle is of a Venetian-blind configuration.

19. The portal monitor of claim 18, wherein said background radiation being shielded is low energy gamma, alpha or beta.

17. A portal monitor for detecting radiation from a target, comprising:

at least one panel, each said panel including an array having;

at least one detector capable of detecting both low and high energy gamma radiation;

at least one liquid scintillator-based detector capable of neutron/gamma pulse-shape discrimination to provide spectrometric identification of fast neutrons and low resolution gamma spectra;

at least one detector for thermal neutrons,

at least one plastic scintillator to give enhanced gamma ray sensitivity; and

,

a shielding baffle mounted on each said panel for reducing background radiation interference emanating from at least below said target.

20. A method for real-time radiation detection, comprising:

providing a detector array having a face and including (i) at least one detector capable of detecting both low and high energy gamma radiation, (ii) at least one liquid scintillator-based detector capable of neutron/gamma pulse-shape discrimination to provide spectrometric identification of fast neutrons and low resolution gamma spectra, (iii) at least one detector for thermal neutrons, and (iv) at least one plastic scintillator to give enhanced gamma ray sensitivity, with said face directed at a target;

positioning at least one baffle substantially horizontally against said face of said detector array, said face having a lowest edge and said at least one baffle being at said lowest edge for said baffle to protrude outwardly and transversely across the width said face;

shielding each of (i) to (iv) with said at least one baffle to produce a raw data;

processing said raw data at each detector of said detector array to calibrate and correct said raw data; and

,

yielding an output from said processed data sufficient for the desired identification.