In-field Calibration of a Fast Neutron Collar for the Measurement of Fresh PWR Fuel Assemblies

Technical Report · Fri Apr 17 00:00:00 EDT 2015

DOI:https://doi.org/10.2172/1178313· OSTI ID:1178313

Swinhoe, Martyn Thomas ^[1]; De Baere, Paul ^[2]

---

1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2. European Commission (Luxembourg). Euratom Safeguards

A new neutron collar has been designed for the measurement of fresh LEU fuel assemblies. This collar uses “fast mode” measurement to reduce the effect of burnable poison rods on the assay and thus reduce the dependence on the operator’s declaration. The new collar design reduces effect of poison rods considerably. Instead of 12 pins of 5.2% Gd causing a 20.4% effect, as in the standard thermal mode collar, they only cause a 3.2% effect in the new collar. However it has higher efficiency so that reasonably precise measurements can be made in 25 minutes, rather than the 1 hour of previous collars. The new collar is fully compatible with the use of the standard data collection and analysis code INCC. This report describes the calibration that was made with a mock-up assembly at Los Alamos National Laboratory and with actual assemblies at the AREVA Fuel fabrication Plant in Lingen, Germany.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: AC52-06NA25396
• OSTI ID: 1178313
• Report Number(s): LA-UR-15-22843; TRN: US1500380
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL PROTECTION
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
FAST NEUTRONS
PWR TYPE REACTORS
BURNABLE POISONS
FUEL ASSEMBLIES
CALIBRATION
DESIGN
PRECISION
EFFICIENCY
NEUTRON DETECTORS
CONTROL ELEMENTS