You need JavaScript to view this

The Passive Neutron Enrichment Meter for Uranium Cylinder Assay

Abstract

As fuel cycle technology becomes more prevalent around the world, international safeguards have become increasingly important in verifying that nuclear materials have not been diverted. Uranium enrichment technology is a critical pathway to nuclear weapons development, making safeguards of enrichment facilities especially important. Independently-verifiable material accountancy is a fundamental measure in detecting diversion of nuclear materials. This paper is about a new instrument for uranium cylinder assay for enrichment plant safeguards called the Passive Neutron Enrichment Meter (PNEM). The measurement objective is to simultaneously verify uranium mass and enrichment in Uf6 cylinders. It can be used with feed, product, and tails cylinders. Here, we consider the enrichment range up to 5% {sup 235}U. The concept is to use the Doubles-to-Singles count rate to give a measure of the {sup 235}U enrichment and the Singles count rate to provide a measure of the total uranium mass. The cadmium ratio is an additional signature for the enrichment that is especially useful for feed and tails cylinders. PNEM is a {sup 3}He-based system that consists of two portable detector pods. Uranium enrichment in UF{sub 6} cylinders is typically determined using a gamma-ray-based method that only samples a tiny volume of the cylinder's content  More>>
Authors:
Miller, Karen A.; Menlove, Howard O.; Swinhoe, Martyn T.; Marlow, Johanna B. [1] 
  1. Safeguards Science and Technology Group (N-1), Los Alamos National Laboratory, Los Alamos (United States)
Publication Date:
Dec 15, 2011
Product Type:
Journal Article
Resource Relation:
Journal Name: ESARDA Bulletin; Journal Volume: 46
Subject:
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; CYLINDERS; ENRICHMENT; FUEL CYCLE; MONTE CARLO METHOD; SAFEGUARDS; URANIUM
OSTI ID:
22129296
Country of Origin:
Italy
Language:
English
Other Identifying Numbers:
Journal ID: ISSN 0392-3029; TRN: IT1300137084419
Availability:
Available from https://esarda.jrc.ec.europa.eu/images//Bulletin/Files/B_2011_046.pdf
Submitting Site:
INIS
Size:
page(s) 115-120
Announcement Date:
Sep 19, 2013

Citation Formats

Miller, Karen A., Menlove, Howard O., Swinhoe, Martyn T., and Marlow, Johanna B. The Passive Neutron Enrichment Meter for Uranium Cylinder Assay. Italy: N. p., 2011. Web.
Miller, Karen A., Menlove, Howard O., Swinhoe, Martyn T., & Marlow, Johanna B. The Passive Neutron Enrichment Meter for Uranium Cylinder Assay. Italy.
Miller, Karen A., Menlove, Howard O., Swinhoe, Martyn T., and Marlow, Johanna B. 2011. "The Passive Neutron Enrichment Meter for Uranium Cylinder Assay." Italy.
@misc{etde_22129296,
title = {The Passive Neutron Enrichment Meter for Uranium Cylinder Assay}
author = {Miller, Karen A., Menlove, Howard O., Swinhoe, Martyn T., and Marlow, Johanna B.}
abstractNote = {As fuel cycle technology becomes more prevalent around the world, international safeguards have become increasingly important in verifying that nuclear materials have not been diverted. Uranium enrichment technology is a critical pathway to nuclear weapons development, making safeguards of enrichment facilities especially important. Independently-verifiable material accountancy is a fundamental measure in detecting diversion of nuclear materials. This paper is about a new instrument for uranium cylinder assay for enrichment plant safeguards called the Passive Neutron Enrichment Meter (PNEM). The measurement objective is to simultaneously verify uranium mass and enrichment in Uf6 cylinders. It can be used with feed, product, and tails cylinders. Here, we consider the enrichment range up to 5% {sup 235}U. The concept is to use the Doubles-to-Singles count rate to give a measure of the {sup 235}U enrichment and the Singles count rate to provide a measure of the total uranium mass. The cadmium ratio is an additional signature for the enrichment that is especially useful for feed and tails cylinders. PNEM is a {sup 3}He-based system that consists of two portable detector pods. Uranium enrichment in UF{sub 6} cylinders is typically determined using a gamma-ray-based method that only samples a tiny volume of the cylinder's content and requires knowledge of the cylinder wall thickness. The PNEM approach has several advantages over gamma-ray-based methods including a deeper penetration depth into the cylinder, meaning it can be used with heterogeneous isotopic mixtures of UF{sub 6}. In this paper, we describe a Monte Carlo modelling study where we have examined the sensitivity of the system to systematic uncertainties such as the distribution of UF{sub 6} within the cylinder. We also compare characterization measurements of the PNEM prototype to the expected measurements calculated with Monte Carlo simulations.}
journal = {ESARDA Bulletin}
volume = {46}
journal type = {AC}
place = {Italy}
year = {2011}
month = {Dec}
}