Source-Jerk Analysis Using a Semi-Explicit Inverse Kinetic Technique

Conference · Mon Aug 26 04:00:00 EDT 1985

OSTI ID:5147458

Spriggs, Gregory D. ^[1]; Pederson, Ray A. ^[1]

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1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

A method is proposed for measuring the effective reproduction factor, k, in subcritical systems. The method uses the transient response of a subcritical system to the sudden removal of an extraneous neutron source (i.e., a source jerk). The response is analyzed using an inverse kinetic technique that least-squares fits the exact analytical solution corresponding to a source-jerk transient as derived from the point-reactor model. It has been found that the technique can provide an accurate means of measuring k in systems that are close to critical (i.e., 0.95 < k < 1.0). As a system becomes more subcritical (i.e., k << 1.0) spatial effects can introduce significant biases depending on the source and detector positions. However, methods are available that can correct for these biases and, hence, can allow measuring subcriticality in systems with k as low as 0.5.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Nuclear Criticality Safety Program (NCSP)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 5147458
• Report Number(s): LA-UR-85-3416; CONF-8508105-5; ON: DE86000803
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
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73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALPHA DECAY RADIOISOTOPES
BARYON REACTIONS
CALCULATION METHODS
DATA
EVEN-ODD NUCLEI
EXPERIMENTAL REACTORS
FISSION
HADRON REACTIONS
HEAVY NUCLEI
INFORMATION
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
Integral-Flux Method
KINETICS
MINUTES LIVING RADIOISOTOPES
MULTIPLICATION FACTORS
NEUTRON DENSITY
NEUTRON REACTIONS
NUCLEAR REACTION KINETICS
NUCLEAR REACTIONS
NUCLEI
NUCLEON REACTIONS
NUMERICAL DATA
Neutron Density Level
Nuclear Criticality Safety Program (NCSP)
POWER
Point-Reactor Model
Prompt-Drop Approximation Method
RADIOISOTOPES
REACTION KINETICS
REACTIVITY
REACTORS
RESEARCH AND TEST REACTORS
Reactivity Measurement
SUBCRITICAL ASSEMBLIES
Spatial Effects
THEORETICAL DATA
THERMAL FISSION
TRANSIENTS
URANIUM 235
URANIUM ISOTOPES
YEARS LIVING RADIOISOTOPES