Technique for the identification of dominant delayed neutron precursors.

Conference · Mon Jan 01 04:00:00 EST 2001

OSTI ID:975892

Loaiza, D J ^[1]; Haskin, E ^[2]

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1. David J.
2. Eric

A technique for the identification of delayed neutron precursors has been developed based on the product of cumulative yield and probability of neutron emission. The motivation behind this work is to fix the decay constants of delayed neutrons to those of the dominant delayed neutron precursors. The desirability of identifying a single set of decay constants that would apply to all fissionable isotopes and be independent of the neutron energy spectrum has been addressed by several authors. The main advantages of a fixed-decay constant representation are simplifying the analysis of epithemal and fast reactors with multiple fissioning isotopes, and improving the fit to experimental data while preserving the inferred positive reactivity scale associated with the original six-group representation. It is well known that 27 1 delayed neutron precursors exist, but only a select number of those precursors contribute significantly to the decay of delayed neutron. Using data compiled by England and Rider, which lists fission yield and probability of neutron emission values for the 27 1 known delayed neutron precursors in 32 fissioning systems, thirteen precursors were identified that are consistently dominant for alI fissioning systems.

• Research Organization: Los Alamos National Laboratory
• Sponsoring Organization: DOE
• OSTI ID: 975892
• Report Number(s): LA-UR-01-6612
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
ANNUAL LIMIT OF INTAKE
DECAY
DELAYED NEUTRON PRECURSORS
DELAYED NEUTRONS
FAST REACTORS
FISSION YIELD
NEUTRON EMISSION
NEUTRONS
PROBABILITY