Use of the Known-M Method for NDA of Plutonium Scrap

PDF Version Also Available for Download.

Description

'Plutonium scrap from another Department of Energy site is to be converted at Savannah River Site (SRS) to a form for permanent storage. For accountability and criticality safety, the material must be measured at SRS, and handling restrictions require assay in 9975 shipping drums. A Multiplicity Neutron Counter is available to perform the measurements, but requires about 12 hours per assay, too long to support the measurement schedule. The assay time has been reduced to 2 hours by use of the Known-M method, the first known routine application of Known-M. The approach involves expression of the multiplication in terms of ... continued below

Creation Information

Thompson, R.S. July 22, 1999.

Context

This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. More information about this article can be viewed below.

Who

People and organizations associated with either the creation of this article or its content.

Publisher

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

Contact Us

What

Descriptive information to help identify this article. Follow the links below to find similar items on the Digital Library.

Description

'Plutonium scrap from another Department of Energy site is to be converted at Savannah River Site (SRS) to a form for permanent storage. For accountability and criticality safety, the material must be measured at SRS, and handling restrictions require assay in 9975 shipping drums. A Multiplicity Neutron Counter is available to perform the measurements, but requires about 12 hours per assay, too long to support the measurement schedule. The assay time has been reduced to 2 hours by use of the Known-M method, the first known routine application of Known-M. The approach involves expression of the multiplication in terms of the effective <sup>239</sup>Pu mass and a quadratic polynomial. Because only a few measured values of multiplication were available, values from Monte Carlo neutron transport calculations (using code MCNP) were used. Because the scrap cans have variable fill heights and fill height affects multiplication, an algorithm to correct the effective <sup>239</sup>Pu mass values for that effect was developed. Testing of the Known-M calibration with limited data suggests a 2-sigma uncertainty of about 5 percent. Drums can contain one or two individual scrap cans, and an algorithm for measuring the combined plutonium content in two cans was developed. The Known-M assay calculations will be performed off line using a spreadsheet.'

Subjects

Keywords

STI Subject Categories

Source

  • Institute of Nuclear Materials Management - 40th Mtg., Phoenix, AZ (USA), 26-29 Jul 1999

Language

Item Type

Identifier

Unique identifying numbers for this article in the Digital Library or other systems.

  • Other: DE00009205
  • Report No.: WSRC-MS-99-00137
  • Grant Number: AC09-96SR18500
  • Office of Scientific & Technical Information Report Number: 9205
  • Archival Resource Key: ark:/67531/metadc793604

Collections

This article is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

Reports, articles and other documents harvested from the Office of Scientific and Technical Information.

Office of Scientific and Technical Information (OSTI) is the Department of Energy (DOE) office that collects, preserves, and disseminates DOE-sponsored research and development (R&D) results that are the outcomes of R&D projects or other funded activities at DOE labs and facilities nationwide and grantees at universities and other institutions.

What responsibilities do I have when using this article?

When

Dates and time periods associated with this article.

Creation Date

  • July 22, 1999

Added to The UNT Digital Library

  • Dec. 19, 2015, 7:14 p.m.

Description Last Updated

  • Aug. 2, 2016, 1:16 p.m.

Usage Statistics

When was this article last used?

Yesterday: 0
Past 30 days: 1
Total Uses: 9

Interact With This Article

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

International Image Interoperability Framework

IIF Logo

We support the IIIF Presentation API

Thompson, R.S. Use of the Known-M Method for NDA of Plutonium Scrap, article, July 22, 1999; South Carolina. (https://digital.library.unt.edu/ark:/67531/metadc793604/: accessed May 23, 2019), University of North Texas Libraries, Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.