Effects of Gain Changes on RPM Performance

PDF Version Also Available for Download.

Description

The mission of the U.S. Department of Energy/National Nuclear Security Administration's (DOE/NNSA's) Office of the Second Line of Defense (SLD) is to strengthen the capability of foreign governments to deter, detect, and interdict the illicit trafficking of special nuclear and other radioactive materials across international borders and through the global maritime shipping system. The goal of this mission is to reduce the probability of these materials being fashioned into a weapon of mass destruction or radiological dispersal device that could be used against the United States or its international partners. This goal is achieved primarily through the installation and operation ... continued below

Creation Information

Lousteau, Angela L; York, Robbie Lynn & Livesay, Jake March 1, 2012.

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.

Sponsor

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

Description

The mission of the U.S. Department of Energy/National Nuclear Security Administration's (DOE/NNSA's) Office of the Second Line of Defense (SLD) is to strengthen the capability of foreign governments to deter, detect, and interdict the illicit trafficking of special nuclear and other radioactive materials across international borders and through the global maritime shipping system. The goal of this mission is to reduce the probability of these materials being fashioned into a weapon of mass destruction or radiological dispersal device that could be used against the United States or its international partners. This goal is achieved primarily through the installation and operation of radiation detection equipment at border crossings, airports, seaports, and other strategic locations around the world. In order to effectively detect the movement of radioactive material, the response of these radiation detectors to various materials in various configurations must be well characterized. Oak Ridge National Laboratory (ORNL) investigated two aspects of Radiation Portal Monitor (RPM) settings, based on a preliminary investigation done by the Los Alamos National Laboratory (LANL): source-to-detector distance effect on amplifier gain and optimized discriminator settings. This report discusses this investigation. A number of conclusions can be drawn from the ORNL testing. First, for increased distance between the source and the detector, thus illuminating the entire detector rather than just the center of the detector (as is done during detector alignments), an increase in gain may provide a 5-15% increase in sensitivity (Fig. 4). However, increasing the gain without adjusting the discriminator settings is not recommended as this makes the monitor more sensitive to electronic noise and temperature-induced fluctuations. Furthermore, if the discriminators are adjusted in relation to the increase in gain, thus appropriately discriminating against electronic noise, the sensitivity gains are less than 5% (Fig. 6). ORNL does not consider this slight increase in sensitivity to be a worthwhile pursuit. Second, increasing the ULD will increase sensitivity a few percent (Fig. 7); however, it is not clear that the slight increase in sensitivity is worth the effort required to make the change (e.g., reliability, cost, etc.). Additionally, while the monitor would be more sensitive to HEU, it would also be more sensitive to NORM. Third, the sensitivity of the system remains approximately the same whether it is calibrated to a small source on contact or a large source far away (Fig. 6). This affirms that no changes to the existing calibration procedure are necessary.

Language

Item Type

Identifier

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

  • Report No.: ORNL/TM-2012/58
  • Grant Number: DE-AC05-00OR22725
  • DOI: 10.2172/1038078 | External Link
  • Office of Scientific & Technical Information Report Number: 1038078
  • Archival Resource Key: ark:/67531/metadc829151

Collections

This report 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 report?

When

Dates and time periods associated with this report.

Creation Date

  • March 1, 2012

Added to The UNT Digital Library

  • May 19, 2016, 3:16 p.m.

Description Last Updated

  • June 17, 2016, 2:49 p.m.

Usage Statistics

When was this report last used?

Yesterday: 0
Past 30 days: 0
Total Uses: 6

Interact With This Report

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

Lousteau, Angela L; York, Robbie Lynn & Livesay, Jake. Effects of Gain Changes on RPM Performance, report, March 1, 2012; United States. (digital.library.unt.edu/ark:/67531/metadc829151/: accessed November 20, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.