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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Neutron imaging of inertial confinement fusion implosions

We review experimental neutron imaging of inertial confinement fusion sources, including the neutron imaging systems that have been used in our measurements at the National Ignition Facility. These systems allow measurements with 10 µm resolution for fusion deuterium–deuterium and deuterium–tritium neutron sources with mean radius up to 400 µm, including measurements of neutrons scattered to lower energy in the remaining cold fuel. These measurements are critical for understanding the fusion burn volume and the three-dimensional effects that can reduce the neutron yields.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2021

Congenital Malformations and Perinatal Deaths Among the Children of Atomic Bomb Survivors: A Reappraisal

From 1948 to 1954, the Atomic Bomb Casualty Commission conducted a study of pregnancy outcomes among births to atomic bomb survivors (Hiroshima and Nagasaki, Japan) who had received radiation doses ranging from 0 Gy to near-lethal levels. Past reports (1956, 1981, and 1990) on the cohort did not identify significant associations of radiation exposure with untoward pregnancy outcomes, such as major congenital malformations, stillbirths, or neonatal deaths, individually or in aggregate. We reexamined the risk of major congenital malformations and perinatal deaths in the children of atomic bomb survivors (n = 71,603) using fully reconstructed data to minimize the potential for bias, using refined estimates of the gonadal dose from Dosimetry System 2002 and refined analytical methods for characterizing dose-response relationships. The analyses showed that parental exposure to radiation was associated with increased risk of major congenital malformations and perinatal death, but the estimates were imprecise for direct radiation effects, and most were not statistically significant. Nonetheless, the uniformly positive estimates for untoward pregnancy outcomes among children of both maternal and paternal survivors are useful for risk assessment purposes, although extending them to populations other than the atomic bomb survivors comes with uncertainty as to generalizability.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Brazil in the Global Nuclear Order, 1945-2018

This book is a comprehensive history of Brazil's nuclear activities and diplomacy. The author provides an in-depth explanation of the country's decision to give up the nuclear arms option and to accept nonproliferation norms after decades of opposition.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2020

Transuranic Waste Volume Reduction Methods for Los Alamos National Laboratory

Los Alamos National Laboratory (LANL, or the Lab) is one of the United States’ (U.S.) weapons complex nuclear security laboratories; it is owned by the Department of Energy (DOE) and operated by Triad National Security, LLC. LANL’s mission is to solve national security challenges through scientific excellence, which includes nuclear deterrence and stockpile stewardship. Such activities generate a variety of radioactive waste types, including transuranic (TRU) waste. The National Nuclear Security Administration (NNSA) is under a congressional mandate to produce no fewer than 80 plutonium pits per year by 2030 to meet Department of Defense requirements and support the nuclear deterrent. LANL is responsible for producing at least 30 pits per year by 2026, while the Savannah River Site will produce 50 pits per year by 2030. As of August 2018, the NNSA TRU waste inventory at LANL was at 53% capacity. In order to ensure the nuclear material missions are able to continue uninterrupted, the storage of TRU waste needs to remain below 60% of total capacity. As LANL increases production and prepares to meet the 30 pits per year goal, waste generation will increase substantially. Thus, there is a need to rejuvenate current infrastructure and implement TRU waste reduction methods in the coming years.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2021

High-Altitude Burst Observed at Large Ground Ranges

The rise times computed by the author’s three-dimensional geomagnetic electromagnetic pulse (EMP) code MACSYNC for a high-altitude nuclear burst increase from a fraction of a shake under the burst to tens of shakes at a 1,000 km ground range (one shake equals 10 nanoseconds). Computations for similar geometries with the frequently used one-dimensional spherical EMP codes CHAP and HEMP show similar rise times under the burst, but rise times that are an order-of-magnitude shorter at large ground ranges. This difference is likely due to the inability of these codes to treat the three-dimensional aspect of the slanted EMP incidence on the atmosphere.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2022

Nuclear decisionmaking, complexity and emerging and disruptive technologies: A comprehensive assessment

The complex interactions of emerging and disruptive technologies (EDTs) could significantly impact nuclear decision-making, particular in an escalating regional conventional conflict. Such conflicts may present governments with a range of nuclear decisions: whether to introduce a nuclear dimension to a crisis, whether to cross the nuclear threshold through limited nuclear use, how to respond to a limited nuclear attack, whether to expand the scope and intensity of initial limited attacks, and whether to escalate to an all-out nuclear war. At each decision point, EDTs create potential risks as well as rewards. EDTs are likely to influence the context for nuclear decision-making and the choices between different courses of action. EDTs could impact the context of nuclear decision-making by improving or degrading situational assessment, the ability to deliberate, and the ability to manage one’s nuclear forces. EDTs could influence the choice between nuclear restraint or escalation by affecting the perceived strategic benefits, escalatory risks, and operational requirements associated with different courses of action. Even though particular combinations of EDTs could precipitate nuclear use in some scenarios, they could encourage restraint in others. The impact and relevance of the same combinations of EDTs might be different at various nuclear decision points. The availability of specific combinations of EDTs at different stages of a conflict would also vary because of the attrition and one-time-use nature of some capabilities. In later stages of a conflict, the decision maker’s confidence in different combinations of EDTs would depend on their previous experience in using them. While the interactions of EDTs are likely to bring additional complexity to a nuclear decision-making process, EDTs are also not the only source of complexity. Broader strategic, military, operational, legal, moral, and emotional factors are also likely to play an important role. These factors may dominate decision-making in a range of potential cases.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2021

A Method for Assessing Effectiveness and Technical Capabilities Required for Integrated Deterrence (NSLP-Final Report-Draft2022)

The United States faces an ever-increasingly multi-polar security environment dominated by great power competition with China and a lingering Russian threat as well as from would-be regional hegemons led by ambitions from Iran and North Korea. Our adversaries are pursuing and expanding the strategic means by-which they have an asymmetric offset (e.g., cyber, space, and other modes below the level of armed conflict). To combat and deter against the widening range of hostile actions, the U.S. must have additional capabilities with-which to deter. All of which drives us towards a more thoughtful integrated approach to deterrence, attempting to best align deterrent tools with the adversary actions in order to maximize the credibility of our deterrent. Such an approach complicates our deterrence strategy and demands a methodology to assess whether the U.S. has the deterrent tools necessary to deter the adversarial actions most costly to the U.S. To address this complexity, we create a framework to comprehensively and systematically assess our deterrent tools as qualitatively measured against the adversarial actions we wish to deter. Deterrence is ultimately an operation in the cognitive domain and at the heart of the framework presented here is the fundamental deterrence calculus which we use as the defining measure of whether a tool will credibly deter a given action. We describe the eight levers of the deterrence calculus and distill these levers to four products that are used to qualitatively assess the overall effectiveness of deterrence tools against adversarial actions. Credibility is determined by two principal variables: the technical credibility of the deterrent tool, and the principle of proportionality. Technical credibility of realized deterrence products is assessed through development of key mission requirements and hardware (e.g., components) that will impose costs, deny benefits, or encourage restraint. The principle of proportionality qualitatively asserts that for a deterrent tool to be cognitively credible, the costs imposed against, or benefits denied by, an action are commensurate to the magnitude of costs received from the adversarial action. By basing this framework on these two fundamentals, it is possible to compare deterrent tools in a systematic approach across the broad spectrum of hostile actions.

42 ENGINEERING↗
DOE OSTI2022

Evaluation of Building 23-620, Los Alamos Scientific Laboratory J-3 Office, Nevada National Security Site, Nye County, Nevada

The U.S. Department of Energy (DOE) National Nuclear Security Administration Nevada Field Office (NNSA/NFO) plans to demolish Building 23-620, the Los Alamos Scientific Laboratory (LASL) J-3 Office Building (Nevada State Historic Preservation Office [SHPO] Resource No. B15283) at the Nevada National Security Site (NNSS) in Nye County, Nevada. The NNSA/NFO is implementing a long-term project to modernize the town of Mercury for future mission needs. The project is considered an undertaking subject to review under Title 54 of United States Code (USC) § 306108, commonly known as Section 106 of the National Historic Preservation Act, Title 54 USC § 300101, et seq., and its implementing regulations, Title 36 of the Code of Federal Regulations (36 CFR) Part 800. In 2018, Desert Research Institute (DRI) completed an architectural survey of the town of Mercury. This effort resulted in the identification, recordation, and evaluation of the Mercury Historic District (MHD, SHPO Resource No. D230), including the identification of its contributing elements (Reno et al. 2018). The MHD was recommended eligible for listing in the National Register of Historic Places (NRHP, National Register) under the Secretary of the Interior’s (SOI) Significance Criteria A and C, as defined in 36 CFR Part 60.4, as a significant concentration of buildings and structures with a direct and important association with Cold War-era nuclear testing from 1951 through 1992. It has not been evaluated under Criteria B and D to date. As part of a larger modernization program for Mercury, the NNSA/NFO and the SHPO executed the 2018 Programmatic Agreement between the National Nuclear Security Administration Nevada Field Office and the Nevada State Historic Preservation Officer regarding Modernization and Operational Maintenance of the Nevada National Security Site, at Mercury in Nye County, Nevada (Mercury PA). The Mercury PA includes streamlined Section 106 procedures for undertakings in the MHD based on contributing element categories. Building 23-620 is identified in Appendix C of the Mercury PA as a Category I contributing element, indicating that it might be individually eligible for the NRHP. It is a historic property for the purposes of Section 106 compliance and subject to the stipulations of the Mercury PA. Per Stipulation VI of the Mercury PA, when the Area of Potential Effect (APE) for an undertaking includes Category I elements, the NNSA/NFO must evaluate the Category I elements for individual NRHP eligibility under all of the SOI Significance Criteria prior to initiating any activity that may affect the elements. The purpose of this report is to evaluate Building 23-620 as a potential individually eligible historic property in fulfillment of Stipulation VI of the Mercury PA. The evaluation detailed herein concludes that Building 23-620 is not individually eligible for listing in the NRHP. Although it retains aspects of integrity and continues to contribute to the MHD, it is not individually significant under any of the SOI Significance Criteria.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Survey of U.S. Research Reactor Auxiliary Facilities Used for Material Testing and Basic Neutron Science

A catalogue of and attributes of the Materials Irradiation and Testing facilities (MIF) and the Basic Neutron Science facilities (BSF) of auxiliary (AUX) facilities of research reactors are compiled. The survey of these facilities is drawn from the set of U.S. university and DOE research reactor facilities and should be considered as a reference point when comparing commonalities in international AUX facilities. The size and shielding capabilities of the facilities, the typical characterization equipment used, and the neutron flux and irradiation capabilities of the facilities are listed. Short descriptions of experimental activities and current practices are detailed for MIFs and BSFs. The attributes are important in consideration of the reconfiguration of the facilities for purposes other than stated mission, i.e., for proliferation of weapons-usable nuclear material (WUNM). An evaluation of the capacity for production rate of WUNM from neutron beams-on-targets or a sample that has been placed in an irradiation position for a period is provided. Further evaluation of reconfiguration of these MIF and BSF are recommended to refine the proliferation risks. Specifically, MIF hot cells and potential configurations, additional modeling of facility throughput and development of methods for determining levels of concern for MIF and BSF have all been identified as steps for refinement of determination of the risks associated with these facilities. Future work will focus on: 1. A model of projected throughput for different MIF and BSF configurations that will be used to provide a window of potential operational misuse for a facility and better understand the capability of production and the rate of processing for WUNM in these facilities. 2. A misuse study for various configurations of MIF hot cell layouts detailing capacity, specifications, shielding constraints for MIF operations, identification of a maximum shielding thickness, and reasonable need associated with each activity performed in a MIF. 3. Development of a rule of thumb rating system utilizing data gathered from previous reports to show levels of concern at a given power level, flux, and experiment set.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2025

S&TR Oct/Nov 2025 Research SLAM! issue

Postdoctoral research offers value to Lawrence Livermore’s scientific and technological efforts. Uplifting early-career researchers as the next generation of scientists benefits their futures and the Laboratory’s. Taking inspiration from the University of California Grad Slam, which challenges participants to explain their theses in three minutes, the Research SLAM at Livermore provides postdoctoral researchers an opportunity to share their research while honing their communication skills and preparing them for a career in collaborative science. The first spinoff of the Livermore SLAM extended the competition to all Department of Energy (DOE) national laboratories in the San Francisco Bay Area. A competition among DOE national laboratories across the country has followed, spurring a nationwide appreciation for budding scientists and the art of connecting high-level science with the nonexpert.

organic↗
DOE OSTI2020

Chemical Fractionation is not a Constant: Revisiting Bomb Vapor Chemistry

The debris produced by a nuclear explosion forms a hazard to response, can serve as a record used to interpret the event, and may persist in the environment necessitating long term management. Hence, understanding the radiochemical inventory of nuclear debris remains an important area of study, particularly the behavior and resulting distribution of actinides and fission products. Despite formation in a high energy environment, it has been recognized for decades that the chemical and isotopic composition of debris rarely, if ever, captures a homogenized blend of the bomb products. Instead, during cooling and debris formation, a variety of chemical processes cause separation of the different constituents. This process of chemical fractionation creates debris with a variety of different radionuclide inventories. Here we provide an overdue re-examination of our historic basis for understanding chemical fractionation in nuclear explosions through the context of new characterization of a large set of historical nuclear test data. Finally, we then discuss the implications of our findings for advancing models of radionuclide distribution and postdetonation chemical fractionation.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗