Neutron Beam Characterization at Neutron Radiography (NRAD) Reactor East Beam Following Reactor Modifications

The Neutron Radiography Reactor at Idaho National Laboratory (INL) has two beamlines extending radially outward from the east and north faces of the reactor core. The control rod withdrawal procedure has recently been altered, potentially changing power distribution of the reactor and thus the prope...

Full description

Saved in:
Bibliographic Details
Published inQuantum beam science Vol. 5; no. 2; p. 8
Main Authors Giegel, Sam H., Craft, Aaron E., Papaioannou, Glen C., Smolinski, Andrew T., Pope, Chad L.
Format Journal Article
LanguageEnglish
Published Basel MDPI AG 01.06.2021
Subjects
Algorithms
Aluminum
beam characterization
Cadmium
Control rods
Electric power distribution
Energy spectra
Fast neutrons
Gold
Image quality
Measurement techniques
Metal foils
Monte Carlo simulation
neutron beam
Neutron beams
Neutron flux
neutron imaging
Neutron radiography
Neutrons
Radiography
Sample variance
Standard deviation
Online AccessGet full text

Cover

More Information
Summary:The Neutron Radiography Reactor at Idaho National Laboratory (INL) has two beamlines extending radially outward from the east and north faces of the reactor core. The control rod withdrawal procedure has recently been altered, potentially changing power distribution of the reactor and thus the properties of the neutron beams, calling for characterization of the neutron beams. The characterization of the East Radiography Station involved experiments used to measure the following characteristics: Neutron flux, neutron beam uniformity, cadmium ratio, image quality, and the neutron energy spectrum. The ERS is a Category-I neutron radiography facility signifying it has the highest possible rank a radiography station can achieve. The thermal equivalent neutron flux was measured using gold foil activation and determined to be 9.61 × 106 ± 2.47 × 105 n/cm2-s with a relatively uniform profile across the image plane. The cadmium ratio measurement was performed using bare and cadmium-covered gold foils and measured to be 2.05 ± 2.9%, indicating large epithermal and fast neutron content in the beam. The neutron energy spectrum was measured using foil activation coupled with unfolding algorithms provided by the software package Unfolding with MAXED and GRAVEL (UMG). The Monte-Carlo N-Particle (MCNP6) transport code was used to assist with the unfolding process. UMG, MCNP6, and measured foil activities were used to determine a neutron energy spectrum which was implemented into the MCNP6 model of the east neutron beam to contribute to future studies.
ISSN:2412-382X
2412-382X
DOI:10.3390/qubs5020008