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Title: A Time-Measurement System Based on Isotopic Ratios.

Abstract

A time-measurement system can be built based on the ratio of gamma-ray peak intensities from two radioactive isotopes. The ideal system would use a parent isotope with a short half-life decaying to a long half-life daughter. The activities of the parent-daughter isotopes would be measured using a gamma-ray detector system. The time can then be determined from the ratio of the activities. The best-known candidate for such a system is the {sup 241}Pu-{sup 241}Am parent-daughter pair. However, this {sup 241}Pu-{sup 241}Am system would require a high-purity germanium detector system and sophisticated software to separate and distinguish between the many gamma-ray peaks produced by the decays of the two isotopes. An alternate system would use two different isotopes, again one with a short half-life and one with a half-life that is long relative to the other. The pair of isotopes {sup 210}Pb and {sup 241}Am (with half-lives of 22 and 432 years, respectively) appears suitable for such a system. This time-measurement system operates by measuring the change in the ratio of the 47-keV peak of {sup 210}Pb to the 60-keV peak of {sup 241}Am. For the system to work reasonably well, the resolution of the detector would need to be suchmore » that the two gamma-ray peaks are well separated so that their peak areas can be accurately determined using a simple region-of-interest (ROI) method. A variety of detectors were tested to find a suitable system for this application. The results of these tests are presented here.« less

Authors:
;  [1];  [2];  [3]
  1. (Peter J.)
  2. (Duncan W.)
  3. (Jonathan L.)
Publication Date:
Research Org.:
Los Alamos National Laboratory
Sponsoring Org.:
USDOE
OSTI Identifier:
978014
Report Number(s):
LA-UR-07-3782
TRN: US1003781
Resource Type:
Conference
Resource Relation:
Conference: Proceeding of the 48th Annual Meeting of The Institute of Nuclear Materials Management, Tucson, Arizona, USA, July 8-12, 2007.
Country of Publication:
United States
Language:
English
Subject:
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; GE SEMICONDUCTOR DETECTORS; HALF-LIFE; NUCLEAR MATERIALS MANAGEMENT; RESOLUTION; TIME MEASUREMENT

Citation Formats

Vo, Duc T., Karpius, P. J., MacArthur, D. W., and Thron, J. L. A Time-Measurement System Based on Isotopic Ratios.. United States: N. p., 2007. Web.
Vo, Duc T., Karpius, P. J., MacArthur, D. W., & Thron, J. L. A Time-Measurement System Based on Isotopic Ratios.. United States.
Vo, Duc T., Karpius, P. J., MacArthur, D. W., and Thron, J. L. Mon . "A Time-Measurement System Based on Isotopic Ratios.". United States. doi:. https://www.osti.gov/servlets/purl/978014.
@article{osti_978014,
title = {A Time-Measurement System Based on Isotopic Ratios.},
author = {Vo, Duc T. and Karpius, P. J. and MacArthur, D. W. and Thron, J. L.},
abstractNote = {A time-measurement system can be built based on the ratio of gamma-ray peak intensities from two radioactive isotopes. The ideal system would use a parent isotope with a short half-life decaying to a long half-life daughter. The activities of the parent-daughter isotopes would be measured using a gamma-ray detector system. The time can then be determined from the ratio of the activities. The best-known candidate for such a system is the {sup 241}Pu-{sup 241}Am parent-daughter pair. However, this {sup 241}Pu-{sup 241}Am system would require a high-purity germanium detector system and sophisticated software to separate and distinguish between the many gamma-ray peaks produced by the decays of the two isotopes. An alternate system would use two different isotopes, again one with a short half-life and one with a half-life that is long relative to the other. The pair of isotopes {sup 210}Pb and {sup 241}Am (with half-lives of 22 and 432 years, respectively) appears suitable for such a system. This time-measurement system operates by measuring the change in the ratio of the 47-keV peak of {sup 210}Pb to the 60-keV peak of {sup 241}Am. For the system to work reasonably well, the resolution of the detector would need to be such that the two gamma-ray peaks are well separated so that their peak areas can be accurately determined using a simple region-of-interest (ROI) method. A variety of detectors were tested to find a suitable system for this application. The results of these tests are presented here.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

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