An improved technique for passive neutron assay through the use of extendable dead time and higher moments analysis

Journal Article · Tue May 01 00:00:00 EDT 1990 · JNMM (Journal of the Institute of Nuclear Materials Management); (USA)

OSTI ID:6735585

Degweker, S B ^[1]; Srinivasan, M; Panchal, C G ^[2]

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1. Bhabha Atomic Research Centre, Bombay (India). Reactor Analysis and Systems Div.
2. Bhabha Atomic Research Centre, Bombay (India). Neutron Physics Div.

The high level neutron coincidence counting technique for the non-destructive determination of plutonium in sealed packages has been plagued by complications arising from self-multiplication effects. The authors propose an extension of the techniques developed for the measurement of the degree of subcriticality of highly subcritical systems in the field of reactor noise analysis, to the passive neutron assay problem. It is shown that deployment of a variable dead time filter of the extendable type rather than of the commonly adopted non-extendable type leads to a simple and practical method for measuring the mean, variance and higher moments of the multiplicity distribution of the neutron emitting source and deducing therefrom the spontaneous fission rate, the self-multiplication probability and other parameters. The applicability of the technique is demonstrated using a Cf-252 neutron source.

• OSTI ID: 6735585
• Journal Information: JNMM (Journal of the Institute of Nuclear Materials Management); (USA), Vol. 18:3; ISSN 0893-6188
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
CALIFORNIUM 252
SPONTANEOUS FISSION
PACKAGE REACTORS
NEUTRON DETECTION
PLUTONIUM
NONDESTRUCTIVE TESTING
COINCIDENCE METHODS
NEUTRON SOURCES
SUBCRITICAL ASSEMBLIES
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ACTINIDES
ALPHA DECAY RADIOISOTOPES
CALIFORNIUM ISOTOPES
COUNTING TECHNIQUES
DECAY
DETECTION
ELEMENTS
EVEN-EVEN NUCLEI
EXPERIMENTAL REACTORS
FISSION
HEAVY NUCLEI
ISOTOPES
MATERIALS TESTING
METALS
NUCLEAR DECAY
NUCLEAR REACTIONS
NUCLEI
PARTICLE SOURCES
POWER REACTORS
RADIATION DETECTION
RADIATION SOURCES
RADIOISOTOPES
REACTORS
RESEARCH AND TEST REACTORS
TESTING
TRANSPORTABLE REACTORS
TRANSURANIUM ELEMENTS
YEARS LIVING RADIOISOTOPES
220100* - Nuclear Reactor Technology- Theory & Calculation
220700 - Nuclear Reactor Technology- Plutonium & Isotope Production Reactors
652020 - Nuclear Properties & Reactions
A=220 & above
Experimental
653006 - Nuclear Theory- Spontaneous & Induced Fission