Analysis of fissile materials by cyclic activation of delayed neutrons

Journal Article · Thu Jun 01 04:00:00 EDT 1978 · Nucl. Technol.; (United States)

OSTI ID:6212893

Jamieson, J M; Eichholz, G G

A method for analyzing nuclear material developed and tested with samples of /sup 235/U and /sup 239/Pu, singly and in combination is discussed. The method is based on differences in the abundances and half-lives of delayed neutron groups between the various fissile nuclides. The cyclic activation was accomplished by moving the samples containing fissile material cyclically through a thermal-neutron beam from the Georgia Tech Research Reactor, out of the beam and through a delayed neutron detector, and back through the beam, etc. The delayed neutron response was recorded at activation cycle periods ranging from 0.1 to 100 s for samples containing varying amounts of /sup 235/U and /sup 239/Pu. Deviations in the responses of the samples containing both /sup 235/U and /sup 239/Pu from the response of standards containing only /sup 235/U or /sup 239/Pu were determined to infer the /sup 235/U-to-/sup 239/Pu ratio. After the ratio of the two fissile nuclides present was obtained, the delayed neutron response at short cycle periods was used to estimate the mass of each fissile nuclide present in the sample. For samples containing about a gram of fissile material, accuracies on the order of 2% for /sup 235/U and 4% for /sup 239/Pu could be obtained for 1.5-h experiment run times when the fissile nuclides were present in about equal portions. Accuracies were dependent on the /sup 235/U-to-/sup 239/Pu ratio and on the total mass of fissile materials present. (6 figures)

• Research Organization: Georgia Inst. of Tech., Atlanta
• OSTI ID: 6212893
• Journal Information: Nucl. Technol.; (United States), Journal Name: Nucl. Technol.; (United States) Vol. 39:1; ISSN NUTYB
• Country of Publication: United States
• Language: English

Related Subjects

055001 -- Nuclear Fuels-- Safeguards
Inspection
& Accountability-- Technical Aspects
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400101* -- Activation
Nuclear Reaction
Radiometric & Radiochemical Procedures
98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL PROTECTION
ACCURACY
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ACTIVATION ANALYSIS
ALPHA DECAY RADIOISOTOPES
BARYONS
CHARGED-PARTICLE ACTIVATION
CHEMICAL ANALYSIS
DELAYED NEUTRON ANALYSIS
DELAYED NEUTRONS
ELEMENTARY PARTICLES
EVEN-ODD NUCLEI
FERMIONS
FISSILE MATERIALS
FISSION NEUTRONS
FISSIONABLE MATERIALS
HADRONS
HEAVY NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MINUTES LIVING RADIOISOTOPES
NEUTRONS
NONDESTRUCTIVE ANALYSIS
NUCLEAR REACTION ANALYSIS
NUCLEI
NUCLEONS
PHOTON ACTIVATION ANALYSIS
PLUTONIUM 239
PLUTONIUM ISOTOPES
RADIOISOTOPES
URANIUM 235
URANIUM ISOTOPES
YEARS LIVING RADIOISOTOPES