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Mechanically Cooled Large-Volume Germanium Detector Systems for Neclear Explosion Monitoring DOENA27323-2

Description: Compact maintenance free mechanical cooling systems are being developed to operate large volume high-resolution gamma-ray detectors for field applications. To accomplish this we are utilizing a newly available generation of Stirling-cycle mechanical coolers to operate the very largest volume germanium detectors with no maintenance. The user will be able to leave these systems unplugged on the shelf until needed. The maintenance-free operating lifetime of these detector systems will exceed 5 years. Three important factors affect the operation of mechanically cooled germanium detectors: temperature, vacuum, and vibration. These factors will be studied in the laboratory at the most fundamental levels to insure a solid understanding of the physical limitations each factor places on a practical mechanically cooled germanium detector system. Using this knowledge, mechanically cooled germanium detector prototype systems will be designed and fabricated.
Date: October 30, 2006
Creator: Hull, E.L.
Partner: UNT Libraries Government Documents Department

Mechanically Cooled Large-Volume Germanium Detector Systems for Nuclear Explosion Monitoring DOENA27323-1

Description: Compact maintenance free mechanical cooling systems are being developed to operate large volume germanium detectors for field applications. To accomplish this we are utilizing a newly available generation of Stirling-cycle mechanical coolers to operate the very largest volume germanium detectors with no maintenance. The user will be able to leave these systems unplugged on the shelf until needed. The flip of a switch will bring a system to life in ~ 1 hour for measurements. The maintenance-free operating lifetime of these detector systems will exceed 5 years. These features are necessary for remote long-duration liquid-nitrogen free deployment of large-volume germanium gamma-ray detector systems for Nuclear Explosion Monitoring. The Radionuclide Aerosol Sampler/Analyzer (RASA) will greatly benefit from the availability of such detectors by eliminating the need for liquid nitrogen at RASA sites while still allowing the very largest available germanium detectors to be reliably utilized.
Date: July 28, 2006
Creator: Hull, E.L.
Partner: UNT Libraries Government Documents Department

A Statistical Model and Computer program for Preliminary Calculations Related to the Scaling of Sensor Arrays

Description: Recent advances in sensor technology and engineering have made it possible to assemble many related sensors in a common array, often of small physical size. Sensor arrays may report an entire vector of measured values in each data collection cycle, typically one value per sensor per sampling time. The larger quantities of data provided by larger arrays certainly contain more information, however in some cases experience suggests that dramatic increases in array size do not always lead to corresponding improvements in the practical value of the data. The work leading to this report was motivated by the need to develop computational planning tools to approximate the relative effectiveness of arrays of different size (or scale) in a wide variety of contexts. The basis of the work is a statistical model of a generic sensor array. It includes features representing measurement error, both common to all sensors and independent from sensor to sensor, and the stochastic relationships between the quantities to be measured by the sensors. The model can be used to assess the effectiveness of hypothetical arrays in classifying objects or events from two classes. A computer program is presented for evaluating the misclassification rates which can be expected when arrays are calibrated using a given number of training samples, or the number of training samples required to attain a given level of classification accuracy. The program is also available via email from the first author for a limited time.
Date: April 1, 2001
Creator: Morris, Max
Partner: UNT Libraries Government Documents Department

Nonproliferation through international lab-to-lab technology cooperation

Description: At the Lawrence Livermore National Laboratory (LLNL) one of the fastest growing programs as a result of the end of the Cold War is the Nonproliferation, Arms Control, and International Security Directorate (NAI). Since the early 1990's NAI types of programs have grown from a small percentage of LLNL's budget to constitute one of its major programs. NAI's work includes developing instruments to detect chemicals and radiation, analyzing complex national defense problems, anticipating threats to the US, and providing personnel to support national and international efforts in crisis management and arms control. These functions support the US government in dealing with weapons-of-mass-destruction challenges� proliferation, terrorism, and nuclear-state instability. To combat the rapidly emerging chem-bio-terrorism threats, NAI is drawing on LLNL�s advanced technologies in bioscience, microfabrication, and computations to help the Department of Energy (DOE )provide major support to the US government. Half of NAI's effort is directed toward preventing proliferation before it starts, which is the mission of the Proliferation Prevention and Arms Control Program (PPAC). Until recently, our emphasis was on arms control. Now, arms control continues to be an important component while international cooperation and fissile material control are our dominant activities for the Department of Energy. Many of the post-Cold-War changes are highly visible, such as the elimination of nuclear testing by the United States, Russia, China and other major powers; agreements and continuing negotiations to dramatically reduce numbers of nuclear weapons; and increasing international focus on nonproliferation and counterterrorism. Other changes are less highly publicized but are no less significant. One such area is the increasing interactions between DOE Laboratory scientists and their counterparts in the nuclear weapons institutes of the former Soviet Union. Although the large majority of these Lab-to- Lab activities are currently with the FSU, that experience is leading to important and productive ...
Date: September 10, 1998
Creator: Dunlop, W H
Partner: UNT Libraries Government Documents Department

Chemical and biological nonproliferation program. FY99 annual report

Description: This document is the first of what will become an annual report documenting the progress made by the Chemical and Biological Nonproliferation Program (CBNP). It is intended to be a summary of the program's activities that will be of interest to both policy and technical audiences. This report and the annual CBNP Summer Review Meeting are important vehicles for communication with the broader chemical and biological defense and nonproliferation communities. The Chemical and Biological Nonproliferation Program Strategic Plan is also available and provides additional detail on the program's context and goals. The body of the report consists of an overview of the program's philosophy, goals and recent progress in the major program areas. In addition, an appendix is provided with more detailed project summaries that will be of interest to the technical community.
Date: March 1, 2000
Partner: UNT Libraries Government Documents Department

Low Noise Borehole Triaxial Seismometer Phase II

Description: This report describes the preliminary design and the effort to date of Phase II of a Low Noise Borehole Triaxial Seismometer for use in networks of seismic stations for monitoring underground nuclear explosions. The design uses the latest technology of broadband seismic instrumentation. Each parameter of the seismometer is defined in terms of the known physical limits of the parameter. These limits are defined by the commercially available components, and the physical size constraints. A theoretical design is proposed, and a preliminary prototype model of the proposed instrument has been built. This prototype used the sensor module of the KS2000. The installation equipment (hole locks, etc.) has been designed and one unit has been installed in a borehole. The final design of the sensors and electronics and leveling mechanism is in process. Noise testing is scheduled for the last quarter of 2006.
Date: November 6, 2006
Creator: Kerr, James D & McClung, David W
Partner: UNT Libraries Government Documents Department

Development of Research Infrastructure in Nevada for the Exploitation of Hyperspectral Image Data to Address Proliferation and Detection of Chemical and Biological Materials.

Description: This research was to exploit hyperspectral reflectance imaging technology for the detection and mapping variability (clutter) of the natural background against which gases in the atmosphere are imaged. The natural background consists of landscape surface cover composed of consolidated rocks, unconsolidated rock weathering products, soils, coatings on rock materials, vegetation, water, materials constructed by humans, and mixtures of the above. Human made gases in the atmosphere may indicate industrial processes important to detecting non-nuclear chemical and biological proliferation. Our research was to exploit the Visible and Near-Infrared (NIR) and the Short-wave Infrared (SWIR) portions of the electromagnetic spectrum to determine the properties of solid materials on the earth’s surface that could influence the detection of gases in the Long-Wave Infrared (LWIR). We used some new experimental hyperspectral imaging technologies to collect data over the Non-Proliferation Test and Evaluation Center (NPTEC) located on the Nevada Test Site (NTS). The SpecTIR HyperSpecTIR (HST) and Specim Dual hyperspectral sensors were used to understand the variability in the imaged background (clutter), that detected, measured, identified and mapped with operational commercial hyperspectral techniques. The HST sensors were determined to be more experimental than operational because of problems with radiometric and atmospheric data correction. However the SpecTIR Dual system, developed by Specim in Finland, eventually was found to provide cost-effective hyperspectral image data collection and it was possible to correct the Dual system’s data for specific areas. Batch processing of long flightlines was still complex, and if comparison to laboratory spectra was desired, the Dual system data still had to be processed using the empirical line method. This research determined that 5-meter spatial resolution was adequate for mapping natural background variations. Furthermore, this research determined that spectral resolution of 10um was adequate, but a signal to noise above 300:1 was desirable for hyperspectral sensors with this ...
Date: December 31, 2007
Creator: Taranik, James V.
Partner: UNT Libraries Government Documents Department

Scientific/Technical Report: Improvement in compensation and crystal growth of cadmium zinc telluride radiation detectors

Description: Comparison of actual accomplishments with goals and objectives: (1) Growth of 12 ingots--Washington State University (WSU) more than met this goal for the project by growing 12 final ingots for the year. Nine of the twelve crystal growth ingots resolved gamma radiation at room temperature. The other three ingots where resistivity of {approx} 3 x 10{sup 8} Ohm*cm for CG32a, CG36, and CG42 lower than expected, however none of these were tried with blocking contacts. All ingots were evaluated from tip to heel. In these three cases, the group III, dopant Aluminum (Al) was not detected to a level to compensate the Cd vacancies in the cadmium zinc telluride (CZT) thus the ingots were lower resistivity. The nine ingots that were successful radiation detectors averaged a bulk resistivity of 1.25 x 10{sup 10} Ohm*cm and with a average {mu}{tau} product for electrons of {approx} 2 x 10{sup -4} cm{sup 2}/V with a 1/4 microsecond shaping time with samples {approx}2 mm in thickness. (2) Attempt new compensations techniques--WSU also met this goal. Several doping schemes were attempted and investigated with various amounts of excess Tellurium added to the growth. The combination of Al and Erbium (Er) were first attempted for these ingots and subsequently CG34 was grown with Al, Er and Holmium. These compensation techniques produced radiation detectors and are currently under investigation. These growths were made with significant different doping levels to determine the affect of the dopants. CG43 was doped with Indium and Er. Indium was introduced instead of Al to determine if Indium is more soluble than Al for CZT and was less oxidized. This may decrease the amount of low resistivity ingots grown by doping with Indium instead of Al. (3) Grow large single crystals--Several changes in approach occurred in the crystal growth furnace. Steps were taken ...
Date: May 19, 2007
Creator: Lynn, Kelvin G. & Jones, Kelly A.
Partner: UNT Libraries Government Documents Department


Description: In this project we have addressed the problem of energy partitioning at distances ranging from very local to regional for various kinds of seismic sources. On the local and regional scale (20-220 km) we have targeted events from the region offshore Western Norway where we have both natural earthquake activity as well as frequent occurrence of underwater explosions carried out by the Norwegian Navy. On the small scale we have focused on analysis of observations from an in-mine network of 16-18 sensors in the Pyhasalmi mine in central Finland. This analysis has been supplemented with 3-D finite difference wave propagation simulations in a realistic mine model to investigate the physical mechanisms that partition seismic energy in the near source region in and around the underground mine. The results from modeling and analysis of local and regional data show that mean S/P amplitude ratios for explosions and natural events differ at individual stations and are in general higher for natural events and frequency bands above 3 Hz. However, the distributions of S/P ratios for explosions and natural events overlap in all analyzed frequency bands. Thus, for individual events in our study area, S/P amplitude ratios can only assist the discrimination between an explosion or a natural event. This observation is supported by synthetic seismograms calculated for simple 1-D models which demonstrate that explosions also generate shear-wave energy if they are fired close to an interface with a strong material contrast (as is the case for most explosions), e.g., free surface or the ocean bottom. The larger difference in S/P ratios between earthquakes and explosions for higher frequencies can be explained by the fact that at low frequencies (larger wavelengths), discontinuities and structural heterogeneities in the explosion source region are stronger generators of converted S energy. The S*-phase, for example, is most ...
Date: January 31, 2006
Creator: Bungum, H.; Kvaerna, T. & Larsen, S.
Partner: UNT Libraries Government Documents Department

U.S. second line of defense: preventing nuclear smuggling across Russia's borders

Description: Preventing the theft of weapons-usable highly enriched uranium and plutonium in Russia is one of the central security concerns facing the US today. The dissolution of the highly centralized USSR and the resulting societal crisis has endangered Russia's ability to protect its more than 200 metric tons of plutonium and 1000 tons of highly enriched uranium (roughly 8 kg Pu or 25 kg HEU is sufficient to make a bomb). Producing this fissile material is the most difficult and expensive part of nuclear weapons production and the US must make every effort to ensure that fissile material (and nuclear-related technologies) does not reach the hands of terrorist groups, rogue states or other potential proliferators. In response to this concern, the US has undertaken a number of initiatives in partnership with Russia and other FSU states to prevent the theft of fissile material. The Material Protection, Control and Accounting Program (MPC&A) was begun in 1993 to prevent the theft of nuclear materials from Russian civilian complexes, that is facilities not under control of the Ministry of Defense, which is largely responsible for possession and oversight of nuclear weapons. The MPC&A program is considered the first line of defense against theft of nuclear material because its goal is to prevent theft of material at production and storage facilities. This year the Department of Energy (DOE) initiated a new program called the Second Line of Defense (SLD), the goal of which is to assist Russia in preventing the smuggling of nuclear material and weapons at its borders, either by land, sea or air. The SLD program represents an important phase in the overall effort to ensure the security of nuclear material and weapons in Russia. However, as the US engages Russian customs officials in this important project, Americans should keep in mind that ...
Date: November 16, 1998
Creator: Ball, D. Y.
Partner: UNT Libraries Government Documents Department

Mechanical Design of Hybrid Densitometer for Laboratory Applications

Description: The hybrid K-edge densitometry (KED) and x-ray fluorescence (XRF) densitometer is a unique nondestructive assay (NDA) technique to determine the concentrations of nuclear material (SNM) in solutions. The technique is ideally suited to assay the dissolver solutions as well as the uranium and plutonium product solutions from reprocessing It is an important instrument for safeguarding reprocessing; it is also a useful tool in analytical laboratories because of its capability of analyzing mixed solutions of SNM without chemical separation. Figure 1 shows the hardware of an hybrid system developed at Los Alamos. The hybrid densitometer employs a combination of two complimentary techniques: absorption KED and XRF. The KED technique measures the transmission of a tightly collimated photon beam through the sample; it is therefore quite insensitive to the radiation emitted by the sample material. Fission product level of {approximately}1 Ci/mL can be tolerated. The technique is insensitive to matrix variation. XRF measures the fluorescent x-rays from the same sample and can be used to determine the ratios of SNM. The technique can be applied to thorium, uranium, neptunium, plutonium, and americium concentration determination. The technique can also be applied to mixed solutions found in nuclear fuel cycle without separation: thorium-uranium, uranium-plutoniun neptunium-plutonium-americium. The design of the hybrid densitometer is shown schematically in Figs. 1 and 2; Fig. 1 shows the top view; Fig. 2 shows the side view. The heart of the design is the changer. The sample changer can accommodate a sample tray, which holds up to six samples. The samples can be a 2-cm path length cell, 4-cm path length cell, or a mixture of both sizes. The sample tray is controlled by a "Compumotor" which in turn is controlled by a computer. The absolute position of the sample cell can be reproduced to a standard deviation of 0.02 ...
Date: January 1, 1999
Creator: Walton, G.; Polk, P. J. & Hsue, S. -T.
Partner: UNT Libraries Government Documents Department

RELAP5-3D code validation for RBMK phenomena

Description: The RELAP5-3D thermal-hydraulic code was assessed against Japanese Safety Experiment Loop (SEL) and Heat Transfer Loop (HTL) tests. These tests were chosen because the phenomena present are applicable to analyses of Russian RBMK reactor designs. The assessment cases included parallel channel flow fluctuation tests at reduced and normal water levels, a channel inlet pipe rupture test, and a high power, density wave oscillation test. The results showed that RELAP5-3D has the capability to adequately represent these RBMK-related phenomena.
Date: September 1, 1999
Creator: Fisher, J.E.
Partner: UNT Libraries Government Documents Department

Isotope Production Facility Conceptual Thermal-Hydraulic Design Review and Scoping Calculations

Description: The thermal-hydraulic design of the target for the Isotope Production Facility (IPF) is reviewed. In support of the technical review, scoping calculations are performed. The results of the review and scoping calculations are presented in this report.
Date: August 1, 1998
Creator: Pasamehmetoglu, K.O. & Shelton, J.D.
Partner: UNT Libraries Government Documents Department

Gamma-ray isotopic analysis development at Los Alamos

Description: This report describes the development history and characteristics of software developed in the Safeguards Science and Technology group at Los Alamos for gamma-ray isotopic analysis. This software analyzes the gamma-ray spectrum from measurements performed on actinide samples (principally plutonium and uranium) of arbitrary size, geometry, and physical and chemical composition. The results are obtained without calibration using only fundamental tabulated nuclear constants. Characteristics of the current software versions are discussed in some detail and many examples of implemented measurement systems are shown.
Date: November 1, 1999
Creator: Sampson, Thomas E.
Partner: UNT Libraries Government Documents Department

The ARAC client system: network-based access to ARAC

Description: The ARAC Client System allows users (such as emergency managers and first responders) with commonly available desktop and laptop computers to utilize the central ARAC system over the Internet or any other communications link using Internet protocols. Providing cost-effective fast access to the central ARAC system greatly expands the availability of the ARAC capability. The ARAC Client system consists of (1) local client applications running on the remote user's computer, and (2) ''site servers'' that provide secure access to selected central ARAC system capabilities and run on a scalable number of dedicated workstations residing at the central facility. The remote client applications allow users to describe a real or potential them-bio event, electronically sends this information to the central ARAC system which performs model calculations, and quickly receive and visualize the resulting graphical products. The site servers will support simultaneous access to ARAC capabilities by multiple users. The ARAC Client system is based on object-oriented client/server and distributed computing technologies using CORBA and Java, and consists of a large number of interacting components.
Date: July 12, 1999
Creator: Leach, M J; Sumikawa, D & Webster, C
Partner: UNT Libraries Government Documents Department

Uncertainty in dispersion forecasts using meteorological ensembles

Description: The usefulness of dispersion forecasts depends on proper interpretation of results. Understanding the uncertainty in model predictions and the range of possible outcomes is critical for determining the optimal course of action in response to terrorist attacks. One of the objectives for the Modeling and Prediction initiative is creating tools for emergency planning for special events such as the upcoming the Olympics. Meteorological forecasts hours to days in advance are used to estimate the dispersion at the time of the event. However, there is uncertainty in any meteorological forecast, arising from both errors in the data (both initial conditions and boundary conditions) and from errors in the model. We use ensemble forecasts to estimate the uncertainty in the forecasts and the range of possible outcomes.
Date: July 12, 1999
Creator: Chin, H N & Leach, M J
Partner: UNT Libraries Government Documents Department

Analysis, comparison, and modeling of radar interferometry, date of surface deformation signals associated with underground explosions, mine collapses and earthquakes. Phase I: underground explosions, Nevada Test Site

Description: We have previously presented simple elastic deformation modeling results for three classes of seismic events of concern in monitoring the CTBT--underground explosions, mine collapses and earthquakes. Those results explored the theoretical detectability of each event type using synthetic aperture radar interferometry (InSAR) based on commercially available satellite data. In those studies we identified and compared the characteristics of synthetic interferograms that distinguish each event type, as well the ability of the interferograms to constrain source parameters. These idealized modeling results, together with preliminary analysis of InSAR data for the 1995 mb 5.2 Solvay mine collapse in southwestern Wyoming, suggested that InSAR data used in conjunction with regional seismic monitoring holds great potential for CTBT discrimination and seismic source analysis, as well as providing accurate ground truth parameters for regional calibration events. In this paper we further examine the detectability and ''discriminating'' power of InSAR by presenting results from InSAR data processing, analysis and modeling of the surface deformation signals associated with underground explosions. Specifically, we present results of a detailed study of coseismic and postseismic surface deformation signals associated with underground nuclear and chemical explosion tests at the Nevada Test Site (NTS). Several interferograms were formed from raw ERS-1/2 radar data covering different time spans and epochs beginning just prior to the last U.S. nuclear tests in 1992 and ending in 1996. These interferograms have yielded information about the nature and duration of the source processes that produced the surface deformations associated with these events. A critical result of this study is that significant post-event surface deformation associated with underground nuclear explosions detonated at depths in excess of 600 meters can be detected using differential radar interferometry. An immediate implication of this finding is that underground nuclear explosions may not need to be captured coseismically by radar images acquired before ...
Date: July 23, 1999
Creator: Foxall, W; Vincent, P & Walter, W
Partner: UNT Libraries Government Documents Department

Extended Evaluations of the Commercial Spectrometer Systems for Safeguards Applications

Description: Safeguards applications require the best of the spectrometer system with excellent resolution, stability, and throughput. Instruments must perform well in all situations and environments. Data communication to the computer should be convenient, fast, and reliable. The software should have all the necessary tools and be easy to use. Portable systems should be small in size, lightweight, and have a long battery life. Nine commercially available spectrometer systems are tested with five different germanium detectors. Considering the performance of the Digital Signal Processors (DSP), digital-based spectroscope y may become the way of future gamma-ray spectroscopy.
Date: August 1, 1999
Creator: Vo, Duc T.
Partner: UNT Libraries Government Documents Department

Edge reclamation in position-sensitive photomultiplier tubes

Description: We have investigated the performance of a position-sensitive, gamma-ray detector based on a CsI(Na) scintillator coupled to a Hamamatsu R3292 Position-Sensitive Photomultiplier Tube (PSPMT). The R3292 has an active area 10.0 cm in diameter (quoted). Utilization of the full active area of the photocathode is a goal that has been previously unrealized due to edge effects. Initial measurements with a 0.75 cm thick CsI(Na) crystal indicate that the performance (position resolution linearity) starts to degrade as one reaches a radius of only 3.5 cm, reducing the active area by 60%. Measuring the anode wires we have found that this fall off is not solely due to crystal edge effects, but rather is inherent to the tube crystal system. In this paper we describe the results of our measurements and how good performance can be maintained across a full 10cm of the tube face through the use of a few additional electronics channels.
Date: June 16, 1999
Creator: Nakae, L & Ziock, K
Partner: UNT Libraries Government Documents Department

Uranium Isotopic Analysis with the FRAM Isotopic Analysis Code

Description: FRAM is the acronym for Fixed-energy Response-function Analysis with Multiple efficiency. This software was developed at Los Alamos National Laboratory originally for plutonium isotopic analysis. Later, it was adapted for uranium isotopic analysis in addition to plutonium. It is a code based on a self-calibration using several gamma-ray peaks for determining the isotopic ratios. The versatile-parameter database structure governs all facets of the data analysis. User editing of the parameter sets allows great flexibility in handling data with different isotopic distributions, interfering isotopes, and different acquisition parameters such as energy calibration and detector type.
Date: May 1, 1999
Creator: Vo, Duc T. & Sampson, Thomas E.
Partner: UNT Libraries Government Documents Department

RELAP/MOD3.2 Assessment Using an 11% Upper Plenum Break Experiment in the PSB Facility

Description: The RELAP/MOD3.2 computer code has been assessed using an 11% upper plenum break experiment in the PSB test facility at the Electrogorsk Research and Engineering Center. This work was performed as part of the U.S. Department of Energy's International Nuclear Safety Program, and is part of the effort addressing the capability of the RELAP5/MOD3.2 code to model transients in Soviet-designed reactors. Designated VVER Standard Problem PSBV1, the test addressed several important phenomena related to VVER behavior that the code needs to simulate well. The code was judged to reasonably model the phenomena of two-phase flow natural circulation in the primary coolant system, asymmetric loop behavior, leak flow, loop seal clearance in the cold legs, heat transfer in a covered core, heat transfer in a partially covered core, pressurizer thermal-hydraulics, and integral system effects. The code was judged to be in minimal agreement with the experiment data for the mixture level and entrainment in the core, leading to a user recommendation to assess the sensitivity of transient calculations to the interphase drag modeling in the core. No judgments were made for the phenomena of phase separation without mixture level formation, mixture level and entrainment in the steam generators, pool formation in the upper plenum, or flow stratification in horizontal pipes because either the phenomenon did not occur in the test or there were insufficient measurements to characterize the behavior.
Date: January 17, 2003
Creator: Bayless, P.D.
Partner: UNT Libraries Government Documents Department

Building a dedicated information barrier system for warhead and sensitive item verification

Description: This paper documents the development of a dedicated information barrier system for warhead and sensitive item verification. The system the authors describe includes software and hardware information barriers used in conjunction with suitable procedures (or protocols) to achieve a high quality verification while minimizing intrusiveness and preventing transfer of sensitive data to inspectors. The system they describe has been referred to as CIVET--Controlled Intrusiveness Verification Technology and has been implemented to verify warheads and warhead components during various exercises and demonstrations under the auspices of the Department of Energy (DOE) and the Department of Defense (DOD).
Date: July 25, 1999
Partner: UNT Libraries Government Documents Department