US 5,606,167 A · Contraband detection apparatus and method

Abstract

A contraband detection system (18) using a single, cone shaped neutron beam determines substances concealed in a sample object by developing total neutron cross section spectra for a plurality of elements, including carbon, nitrogen, oxygen, hydrogen and other potential contraband-indicating elements. A processor (26) performs a contraband determination classification based on the neutron total cross section spectra for the plurality of elements, including hydrogen and elements which do not have peaks in the energy range of interest. The contraband detection system (18) includes a neutron source (20) for producing a pulsed, cone shaped beam of fast white neutrons; a spatial neutron detection array (40); a conveyor system (28) for situating a sample object (29) between the source (20) and the detection array (40); a spectra analysis system (24) for determining the neutron total cross section spectra of elements located in the sample object; and the processor (26). The neutron source (20) produces a pulsed beam (36) of fast white neutrons having sufficient energy range whereby removal of neutrons from the beam caused by the presence of a plurality of contraband-indicating elements can be determined. Various techniques of making contraband classification determinations are also disclosed.

Claims20

Dependent claims

Apparatus for detecting a contraband substance internally located in a sample object, wherein all portions of the sample object may be analyzed simultaneously through the use of a single beam of neutrons, the apparatus comprising:

means for producing a pulsed beam of fast white neutrons from a point source, which beam expands to a conical shape and has sufficient intensity in a range over several MeV, so that a plurality of elements have one or more resonance peaks in such energy range;
means for detecting neutrons, which means includes one or more neutron detectors;
means for measuring the time of flight of neutrons from said point source to the said detecting means;
means for situating a sample object between the neutron producing means and the detecting means at a point at which the said neutron beam has expanded sufficiently to allow neutrons in the beam to contact all portions of the sample object sought to be analyzed;
means for determining the neutron attenuation spectra of each portion of the sample object encompassing a solid angle between said point source and a detector of the said detector means;
and
means for making a classification determination based upon said neutron attenuation spectra regarding a potential contraband substance located in the sample object.

4 more elements

Apparatus for detecting a contraband substance internally located in a sample object, the apparatus comprising:

(1) means for producing a pulsed beam of fast white neutrons from a point source in an energy range over several MeV, so that a plurality of elements, including but not limited to carbon, nitrogen, and oxygen, have one or more resonance peaks in such energy range;
(2) means for detecting neutrons, including neutrons in the said white neutron beam, with or without a sample object in said beam, and for determining which neutrons are not removed from the beam when a sample object is in the beam;
(3) means for situating a sample object between the neutron producing means and the detecting means;
(4) means for evaluating the neutron attenuation spectra for the sample object;
and,
(5) processing means for evaluating the neutron attenuation spectra to determine the potential presence of hydrogen in the sample object, or the presence of other elements in the sample object which do not have a resonance peak in the energy range of interest, where the processing means further uses the neutron attenuation spectra evaluation and the determination of the potential presence of hydrogen or other such element not containing a resonance peak to make a classification determination regarding a potential presence of a contraband substance located in the sample object.

3 more elements

Method of detecting a contraband substance internally located in a sample object, comprising the steps of measuring the neutron attenuation spectra of all portions of a sample object simultaneously, evaluating said neutron attenuation spectra, and making a classification determination on the basis of such neutron attenuation spectra regarding whether there is a contraband substance internally located in the sample object.

(i) an accelerator for generating a pulsed deuteron beam and for directing the pulsed deuteron beam to a target;
(ii) a target with a composition such that impingement of the pulsed deuteron beam produces a single pulsed beam of neutrons which expands in a conical shape from a point source;
(iii) a neutron detector array;
(iv) a conveying system for introducing a sample object, such as a suitcase, between the neutron source and the neutron detector assembly;
(v) a spectra analysis system;
and
(vi) a processor for evaluating the said neutron attenuation spectra for the plurality of contraband-indicating elements and for making a classification determination regarding a potential contraband substance located in the sample object.

4 more elements

Dependencies are inferred from the claim text.

Contraband detection apparatus and method

Life of this patent

Contraband detection apparatus and method

Life of this patent

Abstract

Claims20