MCNP-PoliMi Calculations of Active Neutron Interrogation Measurements of HEU Metal

Conference · Tue Jan 01 04:00:00 EST 2008

OSTI ID:988201

Henkel, James J ^[1]; Mihalczo, John T ^[1]

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1. ORNL

This paper presents a comparison of Monte Carlo Code/MCNP-PoliMi calculations [Ref 1] with measurements of the prompt neutron time behavior after introduction into the highly enriched uranium ({approx}93 wt % {sup 235}U) metal of interrogating neutrons from a time tagged {sup 252}Cf spontaneous fission source or a time and directionally tagged neutrons from a steady state DT neutron generator with an embedded alpha detector [Ref 2]. These measurements used a fast time correlation processor from the nuclear material identification system (NMIS) which measured the time distribution of detection events on a nanosecond time scale (equivalent to a randomly pulsed neutron measurement) and the time distribution of events in one detector after an event in another detector (equivalent to a two-detector Rossi-alpha measurement) [Ref 3]. These calculations of the prompt neutron time behavior were performed to verify the ability of calculational methods and cross sections to predict the results for subcritical experiments.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 988201
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CROSS SECTIONS
DETECTION
DISTRIBUTION
HIGHLY ENRICHED URANIUM
IDENTIFICATION SYSTEMS
NEUTRON GENERATORS
NEUTRONS
PROMPT NEUTRONS
SPONTANEOUS FISSION