Direction-position sensing fast neutron detector

Patent metadata

Field	Value
Publication number	US-9348039-B2
Application number	US-201214365199-A
Country	US
Kind code	B2
Filing date	Dec 13, 2012
Priority date	Dec 14, 2011
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

A directional-position sensing fast neutron sensor system is disclosed. The system includes one or more acoustically tensioned metastable fluid detector (ATMFD) for determining the direction of the source of incident neutron radiation. The system has been used to detect the position of a 1 Ci Pu—Be neutron radiation source. The ATMFD detector is comparable in technical performance with directional fast neutron detector-bank technologies but is significantly more economical, smaller, and has little to no interference from nonneutron background radiation. The ATMFD detector can be used to locate hidden neutron sources and has been used in blind tests to do so. Specifically an ATMFD system (with a 6×10 cm cross-sectional area) provides directional information for incoming neutron radiation from an 8 kg Pu source from a distance of 25 m with a resolution of 11.2° at a 68% confidence within 60 seconds. Position and neutron source image sensing were also demonstrated using two ATMFDs.

First claim

The invention claimed is:

1. A neutron detection system for determining the direction of the source of incident neutron radiation comprising a microprocessor and a detecting chamber system containing at least two axis of symmetry containing a fluid configured with a plurality of detecting transducers for detecting bubbles within the chamber system and acoustic transducers for establishing acoustically tensioned metastable state within the liquid in the chamber system that is radially symmetric along the at least two axis of symmetry; the detecting transducers being configured with the chamber system to receive signals obtained from bubbles in the chamber system and transmit them to a microprocessor, the signals being sufficient to allow the microprocessor configured with an algorithm for determining the three dimensional position of the bubbles in the chamber system to determine the position of bubbles within the chamber; the acoustic transducers being configured with the chamber system to introduce a sound wave into the liquid in the chamber system sufficient to introduce an acoustic metastable state in the liquid sufficient to nucleate bubbles upon exposure to incident neutron radiation, the acoustic metastable state being introduced in response to a signal from a microprocessor; and a microprocessor for identifying in 4π the direction of the source of incident neutron radiation from bubble signals generated within the chamber system.

2. The neutron detection system of claim 1 , wherein the microprocessor for identifying the direction of the source of the incident neutron radiation determines the track of the bubbles through chamber fluid, the origin of the bubbles being in the direction of the source of the neutron radiation.

3. The neutron detection system of claim 1 , wherein the microprocessor for identifying the direction of the source of the incident neutron radiation determines the density of bubble events within the chamber fluid, the denser portion of the gradient being in the direction of the source of the neutron radiation.

4. The neutron detection system of claim 1 , wherein the chamber system is spherical and the direction is in three dimensions.

5. The neutron detection system of claim 1 , wherein the chamber system comprises at least two chambers and the direction is in three dimensions.

6. The neutron detection system of claim 1 , further comprising at least four detecting transducers.

7. The neutron detection system of claim 1 , wherein the device is insensitive to gamma photons.

8. The neutron detection system of claim 1 , wherein the device is insensitive to gamma photons and non-neutron cosmic background radiation.

9. The neutron detection system of claim 1 , further comprising quartz reflectors.

10. The neutron detection system of claim 1 , wherein at least one of the acoustic transducers is a piezoelectric transducer.

11. The neutron detection system of claim 1 , wherein at least one acoustic transducer is a piezoelectric ceramic transducer.

12. The neutron detection system of claim 1 , wherein the chamber system further includes a linear amplifier for sending the acoustic signal to the acoustic transducers.

13. The neutron detection system of claim 1 , wherein the chamber system further includes a linear amplifier for sending the acoustic signal to the acoustic transducers, the signal being a sinusoidal sound wave with respect to the liquid in the chamber.

14. A method for determining the direction of incident radiation comprising obtaining a neutron detection system of claim 1 , applying an acoustic sound wave to induce tension in the fluid such that incident neutron radiation causes a bubble within the fluid, detecting bubbles within the chamber system, and determining the direction of the source of a neutron emitting radiation source.

15. The method for determining the direction of incident radiation of claim 14 , wherein the method comprises obtaining a single chamber system.

16. The method for determining the direction of incident radiation of claim 14 , wherein the method comprises obtaining a multiple chamber system.

17. The method for determining the direction of incident radiation of claim 14 , wherein the event is an audible sound produced by a bubble.

Assignees

• Taleyarkhan Rusi P
• Archambault Brian
• Purdue Research Foundation

Inventors

• Taleyarkhan Rusi P
• Archambault Brian

Classifications

• G01T5/02 Primary

  Processing of tracks; Analysis of tracks · CPC title

• G01T3/00 Primary

  Measuring neutron radiation (G01T5/00 takes precedence) · CPC title

• G01T5/002

  using a combination of several movement of track recording devices · CPC title

• G01T5/06

  Bubble chambers · CPC title