Device for measuring the activity of nuclear isotopes using a self-power detector

Patent metadata

Field	Value
Publication number	US-12366673-B2
Application number	US-202117995387-A
Country	US
Kind code	B2
Filing date	Mar 26, 2021
Priority date	Apr 1, 2020
Publication date	Jul 22, 2025
Grant date	Jul 22, 2025

Abstract

A measuring device for measuring the activity of a specimen of a radioactive isotope is disclosed. The specimen of the radioactive isotope is contained within a capsule. The measuring device comprises an inner enclosure, a gamma-radiation sensitive self-power detector (SPD) positioned around the inner enclosure, and an outer enclosure positioned around the SPD and the inner enclosure. The inner enclosure comprises an internal cavity configured to receive the capsule containing the specimen. The inner enclosure defines a longitudinal axis. The outer enclosure secures the SPD to the inner enclosure such that the SPD does not move during operation and storage of the measuring device.

First claim

What is claimed is:

1. A measuring device for measuring the activity of a specimen of a radioactive isotope, wherein the specimen of the radioactive isotope is contained within a capsule, and wherein the measuring device comprises:
an inner enclosure comprising an internal cavity configured to receive the capsule containing the specimen, wherein the inner enclosure defines a longitudinal axis, wherein the inner enclosure comprises a closed end and an open end opposite the closed end, and wherein the internal cavity is positioned between the closed end and the open end;
a gamma-radiation sensitive self-power detector (SPD) positioned around the inner enclosure; and
an outer enclosure positioned around the SPD and the inner enclosure, wherein the outer enclosure secures the SPD to the inner enclosure such that the SPD does not move during operation and storage of the measuring device.

2. The measuring device of claim 1 , wherein the radioactive isotope is Co-60.

3. The measuring device of claim 1 , wherein at least a portion of the SPD comprises platinum.

4. The measuring device of claim 1 , wherein the inner enclosure defines a first length along the longitudinal axis, wherein the specimen defines a second length along the longitudinal axis, and wherein the first length and the second length are the same.

5. The measuring device of claim 4 , wherein the specimen is positioned relative to the inner enclosure such that the first length and the second length overlap along the longitudinal axis.

6. The measuring device of claim 1 , wherein the inner enclosure comprises an outer surface, and wherein the SPD is positioned around the outer surface of the inner enclosure such that the entirety of the outer surface is covered by the SPD.

7. The measuring device of claim 1 , wherein the inner enclosure comprises an outer surface, and wherein the SPD is wrapped around the outer surface of the inner enclosure in a spiral configuration.

8. The measuring device of claim 7 , wherein the spiral configuration of the SPD is configured to cover the entirety of the outer surface of the inner enclosure.

9. The measuring device of claim 1 , wherein the inner enclosure comprises an outer surface, and wherein the SPD is wrapped around the outer surface of the inner enclosure in a helix configuration.

10. The measuring device of claim 9 , wherein the helix configuration of the SPD is configured to cover the entirety of the outer surface of the inner enclosure.

11. The measuring device of claim 1 , wherein the specimen comprises a specimen length defined along the longitudinal axis, wherein the inner enclosure comprises an outer surface, and wherein the SPD is wrapped around the inner enclosure such that the SPD covers the entirety of the outer surface along the specimen length.

12. A method of measuring the activity of a target specimen comprising a radioactive isotope, wherein the method comprises the steps of:
positioning a plurality of test specimens of a radioactive isotope within an internal cavity of a measuring device one at a time, the measuring device comprising a gamma-sensitive self-power detector (SPD), wherein the activity of each of the test specimens is known;
measuring electrical current within the SPD when each of the test specimens is positioned in the measuring device;
positioning a target specimen of the same radioactive isotope as the test specimens within the internal cavity of the measuring device, wherein the activity of the target specimen is unknown;
measuring electrical current within the SPD when the target specimen is positioned in the measuring device; and
comparing the measured electrical currents of the test specimens to the measured electrical current of the target specimen to determine the activity of the target specimen.

13. The method of claim 12 , further comprising the step of using a linear calibration between the measured electrical currents of the test specimens and the measured electrical current of the target specimen.

14. The method of claim 12 , wherein the radioactive isotope is Co-60.

15. The method of claim 12 , wherein at least a portion of the SPD comprises platinum.

16. The method of claim 12 , wherein the SPD is positioned within the measuring device in a helix shape.

17. The method of claim 12 , wherein the measuring device comprises an enclosure including an open end and a closed end opposite the open end, and wherein the internal cavity is defined between the open end the closed end.

18. The method of claim 12 , wherein the step of measuring electrical current within the SPD when the target specimen is positioned in the measuring device occurs outside of a reactor.

19. A method of measuring the activity of a target specimen comprising a radioactive isotope, wherein the method comprises the steps of:
positioning a target specimen of a radioactive isotope within a measuring device comprising a gamma-sensitive self-power detector (SPD), wherein the activity of the target specimen is unknown, and wherein the SPD comprises a known sensitivity level and a known length;
measuring electrical current of the SPD when the target specimen is positioned in the measuring device; and
determining the activity of the target specimen using the measured electrical current of the SPD, the known sensitivity level of the SPD, and the known length of the SPD.

20. The method of claim 19 , wherein the radioactive isotope is Co-60.

21. The method of claim 19 , wherein at least a portion of the SPD comprises platinum.

22. The method of claim 19 , the SPD is positioned within the measuring device in a helix configuration.

Assignees

• Westinghouse Electric Co Llc

Inventors

• Heibel Michael D
• Prible Michael C

Classifications

• G01T7/005

  calibration techniques (stabilization of spectrometer G01T1/40) · CPC title

• G01T3/006 Primary

  using self-powered detectors (for neutrons as well as for Y- or X-rays), e.g. using Compton-effect (Compton diodes) or photo-emission or a (n,B) nuclear reaction (radioisotopic generators G21H1/00, e.g. G21H1/02, G21H1/04; photo-tubes H01J40/00; thermionic generators H01J45/00) · CPC title