Accession Number:

ADA504084

Title:

Effect of Advanced Synthetically Enhanced Detector Resolution Algorithm on Specificity and Sensitivity of Portable High Purity Germanium Gamma Detector Spectra

Descriptive Note:

Master's thesis

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT/DEPT OF ENGINEERING PHYSICS

Personal Author(s):

Report Date:

2009-06-01

Pagination or Media Count:

108.0

Abstract:

The ability to identify special nuclear material is one of the necessary prevention mechanisms for preventing proliferation of special nuclear materials. Additionally, if a nuclear event were to occur, information about the nuclear material used may be extracted from gamma spectra, provided it is obtained quickly and accurately. This can be made possible with the use of the exceptional resolution of the HPGe detector. This experiment applied the Advanced Synthetically Enhanced Detector Resolution Algorithm ASEDRA to a portable HPGe detectors spectra, to investigate whether improvements in specificity and sensitivity can be obtained. This method has been used to improve performance of NaITl spectra. In this work, measurements of Cd-109, Co-57, Eu-152, Sb-125, Eu-154, and Eu-155 spectra were used as ground truth gamma emissions. The HPGe spectra were analyzed using ASEDRA and ORTECs Genietrademark, a program used by many in the nuclear weapons community for spectroscopy. Genietrademark was used as a benchmark for comparison in this experiment. The number of positive and false positive peaks identified by each program was used for comparison, based on ground truth peaks, which are the thirty-one known peaks based on the sources used in the experiment. The results of this work show that Genietrademark always locates more ground truth peaks than ASEDRA and that ASEDRA identifies fewer false positive peaks than Genietrademark at all but three of the measurement times. In addition, the performance parameter of Genietrademark is higher than ASEDRA at short measurement times, implying that ASEDRA does not provide additional spectral information at shorter measurement times. The application of ASEDRA to experimental spectra does not provide any improvements in specificity or sensitivity, as compared to Genietrademark.

Subject Categories:

  • Chemical, Biological and Radiological Warfare
  • Nuclear Warfare
  • Miscellaneous Detection and Detectors
  • Nuclear Physics and Elementary Particle Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE