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Temporal multispectral and 3D analysis of Cerro de Pasco, Peru

Mining operations across the world often lead to contamination of land, water resources, ecosystems and in some cases, entire communities.Results of recent health and ground sampling studies revealed extensive lead contamination within the populace and around the City of Cerro de Pasco, Peru. Tailings excavated from a large open pit zinc mine in the center of the city have been aggregated in four large stockpiles within close proximity to neighborhoods, schools, and hospitals. Visual comparison of ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) imagery from 2001 and Sentinel-2 imagery from 2018 suggests a size increase in one tailing stockpile in particular near the neighborhood of Paragsha. Due to ongoing mining efforts, the hypothesis motivating the work presented here is that Pb-bearing minerals would be detectable through multispectral analysis, an increase in Pb mineral percent abundance would be observed and tailing stockpile volume would be detectable between 2001 and 2016. This hypothesis is tested using Spectral Angle Mapper (SAM), Adaptive Coherence Estimator (ACE), and Jeffries-Matusita distance calculation on ASTER (2001) and Sentinel-2 (2018) VNIR and SWIR bands. Volume and area estimate of tailing stockpiles were calculated using a photogrammetrically derived point cloud. SAM detected the presence of five Pb-bearing minerals around Cerro de Pasco and Paragsha. The results of the temporal SAM analysis displayed an increase of approximately 17% of Pb-bearing minerals around the greater Cerro de Pasco city area and approximately 11% for the neighborhood of Paragsha. Jeffries-Matusita distance results suggest clear correlation between contamination sources and affected locations. Total tailing stockpile volume was measured to be approximately 200,300,000 m 3 . Volume for Pile 4 was estimated to have increased by approximately 46,000,000 m 3 between 2001 and 2018. Lastly, these presented results will hopefully inspire and guide future remote sensing campaigns, perhaps involving a UAV or aircraft-based hyperspectral instrument.

54 ENVIRONMENTAL SCIENCES↗

NIF Operations Management Plan, August 2011

Lawrence Livermore National Laboratory’s (LLNL) National Ignition Facility (NIF) is a key component of the National Nuclear Security Administration’s (NNSA) Stockpile Stewardship Program, whose purpose is to maintain the safety, reliability, and effectiveness of our nation’s nuclear stockpile without underground nuclear testing. The NIF is crucial to the Stockpile Stewardship Program because it is the only facility that can create the conditions of extreme temperature and pressure—conditions that exist only in stars or in exploding nuclear weapons—that are relevant to understanding how our modern nuclear weapons operate. As such, the NIF’s primary mission is to attain fusion ignition in the laboratory. Fusion ignition not only supports Stockpile Stewardship needs, but also provides the basis for future decisions about fusion’s potential as a long-term energy source. Additionally, NIF provides scientists with access to high-energy-density regimes that can yield new insight and understanding in the areas of astrophysics, hydrodynamics, material properties, plasma physics, and radiative properties. The use of the NIF to support the Stockpile Stewardship Program and the advancement of basic high-energy-density science understanding is planned and managed through program-level execution plans and NIF directorate-level management teams. An example of a plan is the National Ignition Campaign Execution Plan. The NIF Operations Management Plan provides an overview of the NIF Operations organization and describes how the NIF is supported by the LLNL infrastructure and how it is safely and responsibly managed and operated. Detailed information on NIF management of the organization is found in a series of supporting plans, policies, and procedures. A list of related acronyms can be found in Appendix A of this document. The purpose of this document is to provide a roadmap of how the NIF Operations organization functions. It provides a guide to understanding the requirements, document flow down, organizational vision and mission, performance metrics, and interrelationship of the NIF Operations organization with other directorate and laboratory organizations. This document also provides a listing of roles and responsibilities, core processes, procedures, authority matrices, change control boards, and other information necessary for successfully functioning in the NIF Operations organization. This document, the NIF Shot Operations Plan, and the NIF Maintenance Plan together represent the primary documents satisfying our Conduct of Operations compliance requirement.

42 ENGINEERING↗

Advanced Simulation and Computing FY18 Implementation Plan, Rev. 0

The ASC Program continues to improve its unique tools to solve stockpile problems— with a focus on sufficient resolution, dimensionality, and scientific detail—to enable Quantification of Margins and Uncertainties (QMU) and to resolve the increasingly difficult analyses needed for stockpile stewardship. The needs of the Directed Stockpile Work (DSW) and major modernization programs also drive the requirements for simulation and computational resources. These requirements include planned LEPs, stockpile support activities, and mitigation efforts against the potential for technical surprise. All of the weapons within the current stockpile are in some stage of the life extension process. The simulation and computational capabilities are crucial for successful execution of these lifetime extensions and for ensuring NNSA can certify these life-extended weapons without conducting a UGT. Specific work activities and scope contained in this Implementation Plan (IP) represent the full-year annual operating plan for FY18. The Initial IP effective October 1, 2017, should be consistent with: 1) the Department’s Base Table when operating under a Continuing Resolution (CR); and 2) the final signed appropriation or full-year CR once enacted.

97 MATHEMATICS AND COMPUTING↗

Advanced Simulation and Computing FY19 Implementation Plan, Rev. 0

The ASC Program continues to improve its unique tools to solve stockpile problems— with a focus on sufficient resolution, dimensionality, and scientific detail—to enable Quantification of Margins and Uncertainties (QMU) and to resolve the increasingly difficult analyses needed for stockpile stewardship. The needs of the Directed Stockpile Work (DSW) and major modernization programs also drive the requirements for simulation and computational resources. These requirements include planned LEPs, stockpile support activities, and mitigation efforts against the potential for technical surprise. All of the weapons within the current stockpile are in some stage of the life extension process. The simulation and computational capabilities are crucial for successful execution of these lifetime extensions and for ensuring NNSA can certify these life-extended weapons without conducting a UGT. Specific work activities and scope contained in this Implementation Plan (IP) represent the full-year annual operating plan for FY19. The Initial IP, effective August 8, 2018, should be consistent with the Department’s Base Table when operating under a Continuing Resolution (CR). The final IP, effective date TBD, is consistent with the final, enacted appropriation.

97 MATHEMATICS AND COMPUTING↗

The Challenge for Arms Control Verification in the Post-New START World

Nuclear weapon arms control treaty verification is a key aspect of any agreement between signatories to establish that the terms and conditions spelled out in the treaty are being met. Historically, arms control negotiations have focused more on the rules and protocols for reducing the numbers of warheads and delivery systems - sometimes resorting to complex and arcane procedures for counting forces - in an attempt to address perceived or real imbalances in a nation's strategic posture that could lead to instability. Verification procedures are generally defined in arms control treaties and supporting documents and tend to focus on technical means and measures designed to ensure that a country is following the terms of the treaty and that it is not liable to engage in deception or outright cheating in an attempt to circumvent the spirit and the letter of the agreement. As the Obama Administration implements the articles, terms, and conditions of the recently ratified and entered-into-force New START treaty, there are already efforts within and outside of government to move well below the specified New START levels of 1550 warheads, 700 deployed strategic delivery vehicles, and 800 deployed and nondeployed strategic launchers (Inter-Continental Ballistic Missile (ICBM) silos, Submarine-Launched Ballistic Missile (SLBM) tubes on submarines, and bombers). A number of articles and opinion pieces have appeared that advocate for significantly deeper cuts in the U.S. nuclear stockpile, with some suggesting that unilateral reductions on the part of the U.S. would help coax Russia and others to follow our lead. Papers and studies prepared for the U.S. Department of Defense and at the U.S. Air War College have also been published, suggesting that nuclear forces totaling no more than about 300 warheads would be sufficient to meet U.S. national security and deterrence needs. (Davis 2011, Schaub and Forsyth 2010) Recent articles by James M. Acton and others suggest that the prospects for maintaining U.S. security and minimizing the chances of nuclear war, while deliberately reducing stockpiles to a few hundred weapons, is possible but not without risk. While the question of the appropriate level of cuts to U.S. nuclear forces is being actively debated, a key issue continues to be whether verification procedures are strong enough to ensure that both the U.S. and Russia are fulfilling their obligations under the current New Start treaty and any future arms reduction treaties. A recent opinion piece by Henry Kissinger and Brent Scowcroft (2012) raised a number of issues with respect to governing a policy to enhance strategic stability, including: in deciding on force levels and lower numbers, verification is crucial. Particularly important is a determination of what level of uncertainty threatens the calculation of stability. At present, that level is well within the capabilities of the existing verification systems. We must be certain that projected levels maintain - and when possible, reinforce - that confidence. The strengths and weaknesses of the New START verification regime should inform and give rise to stronger regimes for future arms control agreements. These future arms control agreements will likely need to include other nuclear weapons states and so any verification regime will need to be acceptable to all parties. Currently, China is considered the most challenging party to include in any future arms control agreement and China's willingness to enter into verification regimes such as those implemented in New START may only be possible when it feels it has reached nuclear parity with the U.S. and Russia. Similarly, in keeping with its goals of reaching peer status with the U.S. and Russia, Frieman (2004) suggests that China would be more willing to accept internationally accepted and applied verification regimes rather than bilateral ones. The current verification protocols specified in the New START treaty are considered as the baseline case and are contrasted with possible alternative verification protocols that could be effective in a post-New START era of significant reductions in U.S. and other countries nuclear stockpiles. Of particular concern is the possibility of deception and breakout when declared and observed numbers of weapons are below the level considered to pose an existential threat to the U.S. In a regime of very low stockpile numbers, 'traditional' verification protocols as currently embodied in the New START treaty might prove less than adequate. I introduce and discuss a number of issues that need to be considered in future verification protocols, many of which do not have immediate solutions and so require further study. I also discuss alternatives and enhancements to traditional verification protocols, for example, confidence building measures such as burden sharing against the common threat of weapon of mass destruction (WMD) terrorism, joint research and development.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗

Using choice architecture to exploit a university Distinct Urban Mine

Highlights: • More than USD 11 million lie within this UK DUM for small household appliances. • Different collection systems should be established for working or broken appliances. • Consumer behaviour should inform choice architecture. •DUM evaluations should inform future collection system investments. - Abstract: There are widespread concerns regarding the potential future scarcity of ferrous and non-ferrous materials. However, there are already potentially rich reserves of secondary materials via high ownership of Electrical and Electronic Equipment (EEE) in economically-developed nations. Young people are particularly high consumers of EEE, thus university students and campuses may present an opportunity to harness this potential. University Distinct Urban Mines (DUM) may be used to exemplify how potential reserves of secondary metals may be exploited, and could contribute to the transition from a linear to a circular economy. This study aimed to evaluate small household appliances (SHA) DUM from a UK university, with the objectives to identify and quantify student households’ SHA ownership, WEEE recycling, stockpiling and discarding habits amongst student households, assess and evaluate the monetary potential of SHA DUM at UK level, and propose methods to exploit DUM for universities in the UK. To this purpose, a quantitative survey was undertaken to measure students’ ownership and discarding behaviour with respect to SHA. The amounts of ferrous and non-ferrous materials were then estimated and converted to monetary values from secondary materials market data to appraise the SHA DUM overall value. Thirty-five per cent of SHA are discarded in the general refuse. Broken personal care appliances (PCA) tend to be discarded due to hygiene and small size factors. When in working order, SHA tend to be equally reused, recycled or stockpiled. We conclude that a total of 189 tonnes of ferrous and non-ferrous materials were available via discarding or being stockpiled at the University of Southampton. Extrapolated to UK higher education level, discarded and stockpiled SHA represent a potential worth ∼USD 11 million. To initiate DUM exploitation within Higher Education campuses, we suggest improving users’ choice architecture by providing collection methods specific to broken SHA.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Advanced Simulation and Computing FY13 Implementation Plan

The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the surety and reliability of the U.S. nuclear stockpile. The SSP uses nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of experimental facilities and programs, and the computational enhancements to support these programs.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗

Advanced Simulation and Computing Fiscal Year 2016 Implementation Plan, Version 0

The Stockpile Stewardship Program (SSP) is an integrated technical program for maintaining the safety, surety, and reliability of the U.S. nuclear stockpile. The SSP uses nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of experimental facilities and programs, and the computational capabilities to support these programs. The purpose of this IP is to outline key work requirements to be performed and to control individual work activities within the scope of work. Contractors may not deviate from this plan without a revised WA or subsequent IP.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Advanced Simulation and Computing FY20 Implementation Plan (Rev. 0)

The Stockpile Stewardship Program (SSP) is an integrated technical program for maintaining the safety, surety, and reliability of the U.S. nuclear stockpile. The SSP incorporates nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. The suite of data analyzed comes from activities including stockpile surveillance, experimental research, and development and engineering programs. This integrated national program requires the continued use of experimental facilities and the computational capabilities to support the SSP missions. These component parts, in addition to an appropriately scaled production capability, enable the National Nuclear Security Administration (NNSA) to support stockpile requirements. The ultimate goal of the Stewardship Program, and thus the Advanced Simulation and Computing (ASC) Program, is to ensure that the U.S. maintains a safe, secure, and effective strategic deterrent.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

Advanced Simulation and Computing (FY22 Implementation Plan Rev 0)

The DOE National Nuclear Security Administration (NNSA) Stockpile Stewardship Program (SSP) is an integrated technical program for maintaining the safety, surety, and reliability of the U.S. nuclear stockpile. The SSP incorporates nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. The suite of data analyzed comes from activities including stockpile surveillance, experimental research, and development and engineering programs. This integrated national program requires the continued use of experimental facilities and the computational capabilities to support the SSP missions. These component parts, in addition to an appropriately scaled production capability, enable NNSA to support stockpile requirements. The ultimate goal of the SSP, and thus of the Advanced Simulation and Computing (ASC) Program, is to ensure that the U.S. maintains a safe, secure, and effective strategic deterrent. Specific work activities and scope contained in this Implementation Plan (IP) represent the full-year annual operating plan for FY22. The Initial IP, effective , should be consistent with the Department’s Base Table when operating under a Continuing Resolution (CR). The final IP, effective date TBD, is consistent with the final, enacted appropriation.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗

ASC FY2023 Implementation Plan Revision 0

The DOE National Nuclear Security Administration (NNSA) Stockpile Stewardship Program (SSP) is an integrated technical program for maintaining the safety, security, and reliability of the U.S. nuclear stockpile. The SSP incorporates nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. The suite of data analyzed comes from activities including previous nuclear tests, stockpile surveillance, experimental research, and development and engineering programs. This integrated national program requires the continued use of experimental facilities and the computational capabilities to support the SSP missions. These component parts, in addition to an appropriately scaled production capability, enable NNSA to support stockpile requirements. The ultimate goal of the SSP, and thus of the Advanced Simulation and Computing (ASC) Program, is to ensure that the U.S. maintains a safe, secure, and effective strategic deterrent.

97 MATHEMATICS AND COMPUTING↗

Advanced Simulation and Computing: FY25 Implementation Plan

The DOE National Nuclear Security Administration (NNSA) Stockpile Stewardship Program (SSP) is an integrated technical program for maintaining the safety, security, and reliability of the U.S. nuclear stockpile. The SSP incorporates nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. The suite of data analyzed comes from activities including previous nuclear tests, stockpile surveillance, experimental research, and development and engineering programs. This integrated national program requires the continued use of experimental facilities and the computational capabilities to support the SSP missions. These component parts, in addition to an appropriately scaled production capability, enable NNSA to support stockpile requirements. The ultimate goal of the SSP, and thus of the Advanced Simulation and Computing (ASC) program, is to ensure that the U.S. maintains a safe, secure, and effective strategic deterrent.

97 MATHEMATICS AND COMPUTING↗

Sierra/SD – Verification Test Manual – 5.22

Verification and validation (V&V) of scientific computing programs are important at Sandia National Labs due to the expanding role of computational simulation in managing the United States nuclear stockpile. The complexities of structural response calculations used to analyze physical problems, the varieties of codes applied to the calculations, and the importance of accurate predictions when assessing field conditions demand confidence in the consistency and accuracy of computer codes. Confidence in the accuracy of the predictions arising from computer simulations must ultimately be gained through verification and validation. The Sierra salinas structural dynamics analysis code, Sierra/SD, is used at the DOE Laboratories, and in several DOD projects. The roles of Sierra/SD in the qualification of weapon systems and components for normal and hostile environments throughout the Stockpile-to-Target Sequence include to, • Redesign weapon components. • Certify weapon components and systems for target environments such as hypersonic vehicles. • Certify that components will survive the thermal mechanical shock loads associated with hostile environments. • Evaluate current stockpile issues, including issues associated with uncertainty quantification. • Address many other problems that are encountered in stockpile management. The Sierra/SD verification plan is described, and an evolving set of key verification tests are described in detail. The verification tests ensure the correctness of the mathematics and numerical algorithms associated with functionality describing engineering phenomena. Development is in accordance with a set of tailored Software Quality Engineering (SQE) practices. SQE practices guide the overall verification and validation effort.

97 MATHEMATICS AND COMPUTING↗

2015 Stewardship Science Academic Programs Annual

The Stockpile Stewardship Academic Programs (SSAP) are essential to maintaining a pipeline of professionals to support the technical capabilities that reside at the National Nuclear Security Administration (NNSA) national laboratories, sites, and plants. Since 1992, the United States has observed the moratorium on nuclear testing while significantly decreasing the nuclear arsenal. To accomplish this without nuclear testing, NNSA and its laboratories developed a science-based Stockpile Stewardship Program to maintain and enhance the experimental and computational tools required to ensure the continued safety, security, and reliability of the stockpile. NNSA launched its academic program portfolio more than a decade ago to engage students skilled in specific technical areas of relevance to stockpile stewardship. The success of this program is reflected by the large number of SSAP students choosing to begin their careers at NNSA national laboratories.

Stone, Terri↗

Recycle of Am-241 obtained from long term stored plutonium for use in radioisotope power systems - 15035

Pu-238 has been used as a power source for spacecraft since the early days of space exploration. It has proven to be an effective source of power where the use of solar generated power is impractical. Its application for use in spacecraft power systems was developed by the USA and Russia who have spent many $ 100s of millions on its development and production. However, the original facilities for the production of Pu-238 are no longer in use and existing worldwide stockpiles have reduced to levels sufficient for only one or two further missions. Production of Pu-238 requires considerable facilities including a nuclear reactor and reprocessing plants that are very expensive to build and operate. The European Space Agency (ESA) has assessed the options for post-launch power generation in future European space missions and has made the decision to pursue the use of Am-241 as an alternative isotope to power future European Radioisotope Power Systems (RPS). What makes Am-241 attractive for the European market is its 100% isotopically pure production from the decay of Pu-241 in separated civil plutonium stockpiles. Historically, Europe has relied on collaborations with the USA or Russia to access these nuclear power sources. During 2009, the European Space Agency (ESA) funded a project to examine the cost and practicality of establishing a European source of material suitable for Radioisotope Power Systems (RPS). The study concluded that a small number of radioisotopes could be used in RPSs. On further review two leading candidates, Am-241 and Pu-238, were selected for further study. Whilst Pu-238 was recognized as the isotope of choice for use in RPSs, the costs of setting up a European based production facility was prohibitively expensive. Although Am-241 has a number of limitations compared to Pu-238, the much reduced production costs make Am-241 an attractive option for European based production of RPSs. Despite its lower power density of ∼ 0.11 Wth/g, Am-241 is viewed as a potential alternative to Pu-238 because of its availability within the nuclear fuel cycle. During the reprocessing of spent nuclear fuel plutonium is separated as a chemically pure PuO{sub 2} product, containing around 3-11% w/w of the Pu-241 isotope, and placed into storage. During storage the Pu-241 isotope beta decays to Am-241 with a half-life of 14.4 years. {sub 94}{sup 241}Pu → (β 14.4 y) {sub 95}{sup 241}Am. This process has resulted in many 100 kgs of americium growing into the civil plutonium stockpile in the UK; material that is of value in generating heat sources and is able to be recycled. The key benefit of Am-241 as a potential European RPS source isotope is the availability of feed material along with the facilities to process it. It is expected that aged civil PuO{sub 2} will contain 25-50 g Am-241 per kg PuO{sub 2} depending on the source. A conceptual flowsheet using facilities for separating americium from plutonium is expected to produce on average 8.4 kg Am/year. ESA are now following their published road-map of studies to develop flight ready RTGs and RHUs. This has included the development and testing of the flowsheet to be used for production of Am-241. The project has focused on underpinning the conceptual flowsheet, using aged plutonium in NNL's PuMA laboratory. This has underpinned the design of a plant to produce a steady supply of Am-241. The scope of the overall project is 'store to store' - the starting point is aged plutonium currently housed in existing Sellafield stores and the end point is the storage of separated plutonium and americium powders on the Sellafield site. The full scale process is planned to be housed within the NNL's Central Laboratory in an existing facility designed for plutonium active operations. (authors)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Roadmap to MaRIE January 2015

After the decision to end nuclear testing and the inception of the Stockpile Stewardship program, the condition of the stockpile was the primary mission driver. During the first two decades of stewardship, the primary program goal could be described as underwriting the Stockpile-to-Target Sequence (STS), the military requirements on the conditions the nuclear warheads needed to survive and still operate.

36 MATERIALS SCIENCE↗

HedgeHOGS: A Rapid Nuclear Hedge Sizing and Analysis Tool

The U.S. nuclear stockpile hedge is an inventory of non-deployed nuclear warheads and a force structure capable of deploying those warheads. Current guidance is to retain this hedge to mitigate the risk associated with the technical failure of any single warhead type or adverse geopolitical developments that could require augmentation of the force. The necessary size of the hedge depends on the composition of the nuclear stockpile and assumed constraints. Knowing the theoretical minimum hedge given certain constraints is useful when considering future weapons policy. HedgeHOGS, an Excel-based tool, was developed to enable rapid calculation of the minimum hedge size associated with varying active stockpile composition and hedging strategies.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

The Nature of Scatter at the DARHT Facility and Suggestions for Improved Modeling of DARHT Facility

The U.S. Stockpile Stewardship Program [1] is designed to sustain and evaluate the nuclear weapons stockpile while foregoing underground nuclear tests. The maintenance of a smaller, aging U.S. nuclear weapons stockpile without underground testing requires complex computer calculations [14]. These calculations in turn need to be verified and benchmarked [14]. A wide range of research facilities have been used to test and evaluate nuclear weapons while respecting the Comprehensive Nuclear Test-Ban Treaty (CTBT) [2]. Some of these facilities include the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, the Z machine at Sandia National Laboratories, and the Dual Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos National Laboratory. This research will focus largely on DARHT (although some information from Cygnus and the Los Alamos Microtron may be used in this research) by modeling it and comparing to experimental data. DARHT is an electron accelerator that employs high-energy flash x-ray sources for imaging hydro-tests. This research proposes to address some of the issues crucial to understanding DARHT Axis II and the analysis of the radiographic images produced. Primarily, the nature of scatter at DARHT will be modeled and verified with experimental data. It will then be shown that certain design decisions can be made to optimize the scatter field for hydrotest experiments. Spectral effects will be briefly explored to determine if there is any considerable effect on the density reconstruction caused by changes in the energy spectrum caused by target changes. Finally, a generalized scatter model will be made using results from MCNP that can be convolved with the direct transmission of an object to simulate the scatter of that object at the detector plane. The region in which with this scatter model is appropriate will be explored.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗