Enhanced security threat detection

1. A method of enhancing security threat detection, the method comprising:

irradiating a target during an irradiation period with source x-rays from a stationary x-ray source having an end-point energy of at least 88 keV;

enabling motion of the target with respect to the stationary x-ray source during the irradiation period;

detecting resulting x-rays received from the target resulting from the irradiating during the irradiation period;

generating an image of an interior of the target based on the detected, resulting x-rays;

performing analysis of the image for an indication of a weapon;

producing signals representing an energy spectrum of the resulting x-rays;

analyzing the signals for characteristic x-ray fluorescence that can be emitted from lead potentially present in the target;

providing an indication, based on the signals, of a probability of lead ammunition being present in the target; and

outputting an indication of likelihood of a security threat in the target based on the analysis of the image for the indication of a weapon and on the probability of lead ammunition being present.

2. The method of claim 1 , wherein the irradiating is with the source x-rays formed into a fan beam.

3. The method of claim 1 , further comprising forming the source x-rays into a scanning pencil beam.

4. The method of claim 1 , wherein the resulting x-rays include x-rays selected from a group consisting of scattered x-rays that are scattered from the target, transmitted x-rays that are transmitted through the target, and combinations thereof.

5. The method of claim 1 , wherein enabling motion of the target includes causing translational motion of the target with respect to the stationary x-ray source.

6. The method of claim 5 , wherein causing the translational motion of the target includes using a conveyor belt.

7. The method of claim 1 , wherein enabling the motion includes causing rotational motion of the target with respect to the stationary x-ray source.

8. The method of claim 7 , wherein causing the rotational motion includes using a turntable formed of a material substantially transparent to the source x-rays.

9. The method of claim 1 , wherein enabling motion of the target with respect to the stationary x-ray source includes enabling a vehicle to pass through a vehicle portal by the vehicle's own power.

10. The method of claim 1 , wherein detecting resulting x-rays includes using a detector formed at least partly of a material selected from a group consisting of cadmium telluride, cadmium zinc telluride, cesium lead bromide, and combinations thereof.

11. The method of claim 1 , wherein the source x-rays from the stationary x-ray source have an end-point energy of at least 100 keV.

12. The method of claim 1 , further comprising further comprising outputting an alert if the probability of lead ammunition being present in the target exceeds a pre-defined threshold.

13. The method of claim 12 , wherein the outputting the alert is based on both (i) the analysis of signals for the characteristic x-ray fluorescence, and (ii) the analysis of the image for the indication of a weapon.

14. The method of claim 1 , wherein the indication of the probability is limited to binary YES and NO indication options.

15. The method of claim 1 , wherein the indication of the probability is limited to a finite number of percentage brackets.

16. The method of claim 1 , wherein analyzing the signals for characteristic x-ray fluorescence includes analyzing lead fluorescence peak height relative to background.

17. The method of claim 1 , wherein analyzing the signals for characteristic x-ray fluorescence in includes analyzing lead fluorescence peak height relative to Compton peak height.

18. A system for enhanced security threat detection, the system comprising:

a stationary x-ray source configured to irradiate a target with source x-rays having an end-point energy of at least 88 keV during an irradiation period;

a motion enablement feature configured to enable motion of the target with respect to the stationary x-ray source during the irradiation period;

a set of energy-resolving detectors configured to detect resulting x-rays received from the target resulting from the irradiation during the irradiation period and to produce signals representing an energy spectrum of the resulting x-rays;

an image generator configured to generate an image of an interior of the target based on the detected, resulting x-rays; and

an analyzer configured to:

analyze the signals for characteristic x-ray fluorescence that can be emitted from lead potentially present in the target;

provide an indication, based on the signals, of a probability of lead ammunition being present in the target;

perform analysis of the image for an indication of a weapon; and

output an indication of likelihood of a security threat in the target based on the analysis of the image for the indication of a weapon and on the probability of lead ammunition being present.

19. A system for enhanced security threat detection, the system comprising:

means for irradiating a target during an irradiation period with source x-rays from a stationary x-ray source having an end-point energy of at least 88 keV;

means for enabling motion of the target with respect to the stationary x-ray source during the irradiation period;

means for detecting resulting x-rays received from the target resulting from the irradiating during the irradiation period;

means for generating an image of an interior of the target based on the detected, resulting x-rays;

means for performing analysis of the image for an indication of a weapon;

means for producing signals representing an energy spectrum of the resulting x-rays;

means for analyzing the signals for characteristic x-ray fluorescence that can be emitted from lead potentially present in the target;

means for providing an indication, based on the signals, of a probability of lead ammunition being present in the target; and

means for outputting an indication of likelihood of a security threat in the target based on the analysis of the imaged for the indication of a weapon and on the probability of lead ammunition being present.

20. An x-ray scanning system comprising:

an x-ray source configured to irradiate a target with source x-rays having an end-point energy of at least 88 keV during an irradiation period;

a set of energy-resolving detectors configured to detect resulting x-rays received from the target resulting from the irradiation during the irradiation period and to produce energy spectrum signals representative of an energy spectrum of the resulting x-rays;

a set of imaging detectors configured to detect x-rays selected from the group consisting of resulting x-rays that are scattered from the target during the irradiation period, resulting x-rays that are transmitted through the target during the irradiation period, and combinations thereof;

the set of imaging detectors further configured to output imaging signals representative of an x-ray image of an interior of the target;

an image generator configured to generate an image an x-ray image of the interior of the target based on the imaging signals; and

an analyzer configured to analyze the signals for characteristic x-ray fluorescence (XRF) that can be emitted from lead potentially present in the target and to provide an indication, based on the signals, of a probability of lead ammunition being present in the target,

the analyzer further configured to use the probability and the x-ray image to determine a likelihood of a security threat in the target.