Overview of NWIS Software

PDF Version Also Available for Download.

Description

The Nuclear Weapons Identification System (NWIS) is a system that performs radiation signature measurements on objects such as nuclear weapons components. NWIS consists of a {sup 252}Cf fission source, radiation detectors and associated analog electronics, data acquisition boards, and a computer running Windows NT and the application software. NWIS uses signal processing techniques to produce a radiation signature from the radiation emitted from the object. This signature can be stored and later compared to another signature to determine whether two objects are similar. A library of such signatures can be used to identify objects in closed containers as well as ... continued below

Physical Description

29 pages

Creation Information

Mullens, J.A. August 30, 1999.

Context

This report 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 report can be viewed below.

Who

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

Author

Sponsor

Publisher

  • Oak Ridge Y-12 Plant
    Publisher Info: Oak Ridge Y-12 Plant, TN (United States)
    Place of Publication: Tennessee

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 report. Follow the links below to find similar items on the Digital Library.

Description

The Nuclear Weapons Identification System (NWIS) is a system that performs radiation signature measurements on objects such as nuclear weapons components. NWIS consists of a {sup 252}Cf fission source, radiation detectors and associated analog electronics, data acquisition boards, and a computer running Windows NT and the application software. NWIS uses signal processing techniques to produce a radiation signature from the radiation emitted from the object. This signature can be stored and later compared to another signature to determine whether two objects are similar. A library of such signatures can be used to identify objects in closed containers as well as determine attributes such as fissile mass and in some cases enrichment. NWIS uses a {sup 252}Cf source on one side of the object to produce radiation that its detectors measure on the other side of the target (active mode). If the object naturally emits enough radiation, the {sup 252}Cf source is not required (passive mode). The NWIS data acquisition hardware has five detector channels. Each channel receives shaped detector pulses and times those pulses with 1 nanosecond resolution. In active mode measurements one of these channels receives pulses from a detector measuring the {sup 252}Cf source fissions. Thus, for active mode measurements, NWIS has the time of each {sup 252}Cf fission and the subsequent injection of neutrons and gamma rays into the object. The remaining channels receive pulses from the detectors measuring radiation from the object. These detectors record the amount and time of radiation exiting the object. By correlating the radiation events among the source and the other detectors, and among the detectors themselves, a characteristic response of the object to {sup 252}Cf radiation or its own internal radiation is measured. The data acquisition hardware consists of two custom-made boards. The Data Capture and Compression (DCC) board is built around a Gallium Arsine (GaAs) chip designed at ORNL. This chip assigns a time to each pulse received on the five detector channels and passes five compressed streams of time stamp data to the Data Acquisition (DA) board. The DA board performs additional data compression, consolidates the five data streams into one, formats the data, and passes it across the computer's PCI bus into computer memory. The computer processor performs the signal processing required to calculate the signatures and saves the result to disk. Signature analysis software provides the means to manipulate and match signatures in a signature library.

Physical Description

29 pages

Source

  • Other Information: PBD: 30 Aug 1999

Language

Item Type

Identifier

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

  • Report No.: Y/LB-16,017
  • Grant Number: AC05-84OR21400
  • DOI: 10.2172/12635 | External Link
  • Office of Scientific & Technical Information Report Number: 12635
  • Archival Resource Key: ark:/67531/metadc625229

Collections

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

Office of Scientific & Technical Information Technical Reports

What responsibilities do I have when using this report?

When

Dates and time periods associated with this report.

Creation Date

  • August 30, 1999

Added to The UNT Digital Library

  • June 16, 2015, 7:43 a.m.

Description Last Updated

  • May 6, 2016, 2:50 p.m.

Usage Statistics

When was this report last used?

Yesterday: 0
Past 30 days: 0
Total Uses: 4

Interact With This Report

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

Citations, Rights, Re-Use

Mullens, J.A. Overview of NWIS Software, report, August 30, 1999; Tennessee. (digital.library.unt.edu/ark:/67531/metadc625229/: accessed September 24, 2017), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.