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This document ensures that technologies relevant to LL20-ML-AIT-NE-1-PD3TB “AIT-NEO” have been demonstrated to work as intended and at the appropriate technology readiness level. This assessment is intended to offer management tools for understanding and mitigating programmatic risks associated with new technologies being developed under the AIT-NEO effort.
Three important upgrades provide unsurpassed TIMS measurement capabilities 1. HI-VAC (installed 5 of 7 instruments) 2. ATONA Faraday amplification (2 of 7 instrument) 3. Multiple ion-counting system for ultra-low level detection (installed 4 of 7 instruments).
The response of high explosives to shock loading is traditionally measured with a steady loading pressure. In many accident scenarios involving fragment impact, however, a loading duration that is shorter than the build up to detonation may occur. Fragments passing through multiple materials before reaching a high explosive charge may produce loading that is comprised of more than one shock wave. Additionally, the build up to detonation in high explosive corner turning loads the explosive a short duration pressure pulse, since rarefactions can often rapidly overtake the reactive wave. For these reasons, we have studied the response of the insensitive high explosive (IHE) materials PBX 9502 and LX-17 to complex loadings of varied intensity and duration. We refer to a single loading of limited duration as a “thin pulse”, whereas more complex scenarios were studied with an impactor that produces a double shock in the explosive. The following report presents experimental data and analyses of thin pulse shock initiation and double shock experiments designed to guide development of models of Insensitive High Explosives (IHEs) under controlled one-dimensional conditions relevant to accident scenarios and corner turning. Thin pulse shock initiation data on PBX 9502 and LX-17 were obtained under varied pulse duration, pressed density, and temperature conditions in order to probe various parameters essential for the development of a physics-based Cheetah reactive flow hotspot model. In situ pressure gauges provide insight into the degree of reaction in the explosive that are not obtainable with optical PDV measurements or distance measurements such as run to detonation. Double shock data was obtained to inform a Composition Aware Cheetah model which can be applied to any TATB-based IHEs. This model supports efforts to find a new IHE formulation and potentially incorporate new binders into IHE formulations. Simulations of each experiment are included to demonstrate the utility of these focused experiments to developing models of HE behavior. One-dimensional gas gun experiments are essential for characterizing shocked HE behavior and informing HE models.
On February 1, 2019, the United States and Russia withdrew from the three-decades old Intermediate-Range Nuclear Forces (INF) treaty. Events precipitating the withdrawal were allegations by both the United States and Russia of a variety of treaty violations. Until that point, the treaty had been a centerpiece of arms control and a key agreement of the global security architecture. The absence of such a pillar has the potential destabilize the status quo of arms control, creating significant uncertainty in global nuclear stability and security. In this paper, we present a historical review as overture to an analysis on the impacts of this development on force structure. This analysis examines the changes in U.S., Russian, and Chinese nuclear forces which may occur as a result of the treaty's demise. The article concludes with commentary on potential actions to preserve stability in a post-INF world.
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Articles in this issue include: From Ellen's desk; Advances in aerial payload vessels: Spherical aerogel shells hold vacuum; New materials deformation details emerge through combination of neutron and high-energy x-ray diffraction measurements; and Hans Herrmann named 2019 APS Fellow.
Energetic materials comprise explosives, pyrotechnics, and propellants. The science of energetic materials is dedicated to developing a means to predict performance and safety characteristics with high fidelity. This is a particular challenge and is predicated on materials science and engineering, physics, chemistry, and dynamic response in extreme conditions. Fundamental elements of these complicated composite materials remain grand challenges—from the design of high-energy metastable molecules, to the engineering of composite formulations, to the processing parameters that link to safety and performance characteristics in as-yet undetermined ways. Key elements include crystalline mechanics, grain dynamics, multiphase interfaces, thermal and mechanical damage, and failure—all linked to multistep and high-rate chemistry and shock physics. A future revolution in our understanding and predictive capability for energetic materials behavior and responses is dependent upon sustained focus and advances in materials research and development.
Since 1992, the United States has retained confidence in its nuclear weapon stockpile without performing any tests that produce nuclear yield. Instead, it has invested in a stockpile stewardship program (SSP) based on the same approach that was validated through fifty years of experience during the nuclear testing era. As the test moratorium continues and new information becomes available, it is both necessary and appropriate to periodically revisit the question of whether or not nuclear testing should resume. In a recent article by Dr. Mark Schneider, he asserts that the United States should return to nuclear testing to address the issues that negatively affect our country’s nuclear deterrent. A serious, technically informed evaluation of the most significant of the issues Dr. Schneider has raised is provided in this paper. The conclusion of this evaluation is that the strategy of a well-funded SSP coupled with rigorous assessments to identify if there is a specific need for a nuclear test is sound and cost-effective approach. Any decision otherwise needs to take into careful consideration all the classified SSP successes and data pertaining to the particular issues in question.
The theater experience is driven by the big message of nuclear deterrence through successful stockpile stewardship. This job enables other national and global security work with roots going back to the capabilities developed during the Manhattan Project and honed through the history of this successor scientific laboratory. The story that unfolds uses a narrative (traditional film-type approach), although the theater setup would offer immersion and decision-making (audience participation). The idea is to demonstrate how and why the Laboratory continues its mission in maintaining the nation’s stockpile while concurrently enabling the ever-evolving multi-disciplinary science and technology innovations developed for that purpose to take other scientists along vibrant paths.
Abstract not provided.
Sigma Division maintains a unique manufacturing science capability at Los Alamos National Laboratory that has made substantial contributions to weapons component process development for more than 70 years. This mission requires the ability to handle a range of radiological and hazardous materials, work with a variety of metallic and non-metallic components, and process materials systems with elements spanning hydrogen to uranium. Today, Sigma serves as a national resource for uranium research and development, provides hardware for experimental campaigns, supports production by demonstrating modern fabrication technologies, and conducts manufacturing science research primarily for customers across the nuclear weapons complex, including the Department of Energy, National Nuclear Security Administration, and Office of Defense Programs.
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.
Few concepts are more important to our nation than the principle of deterrence. It is at the very core of our national security strategy. Despite its lasting import to our nation, and the rest of the world, we still lack a complete and explicit formulation of the calculus of deterrence. This has, at times, resulted in failed policies costing the Nation lives and wealth. With the ultimate objective of making the Nation more secure, we establish a complete and explicit formulation of deterrence calculus, which consists of eight levers. As it turns out this formulation also applies to the calculus of compellence, and is thus a unifying model of coercive conflict.
A week before Israel bombed Iran’s nuclear facilities, the Director General of the International Atomic Energy Agency (IAEA) Rafael Grossi had lunch with the Financial Times. In the interview, Grossi expressed both optimism and pessimism about the nuclear landscape: he was hopeful about prospects for diplomacy, including with Iran. But he also expressed longer-term concerns about a proliferation cascade and rising nuclear risks, in particular, Russia’s nuclear threats amidst the war in Ukraine. “In the past, this was quite taboo,” he said, “but now people talk about tactical nuclear weapons like something which could be contained or permissible.” Given subsequent events in Iran, along with the expiration of New START in 2026 and expanding nuclear arsenals in Russia and China, pessimism would seem to trump hope for prospects for nuclear disarmament.
According to Webster, a genius is someone who possesses uncommon powers of intellect, particularly the power of invention. Those who call Los Alamos National Laboratory their professional home have a tremendous power of invention — their genius benefits from atomic power. Nuclear weapons are the heart of the Laboratory’s origin story. It is why we are here. They are also central to the multiple innovations inspired and driven by such atomic work — in ways that might surprise you. Our search for solutions outside the realm of nuclear security is nevertheless built on the incredible innovations and challenges driven by a defining moment in our world’s history — the advent of the nuclear weapon.
Above-ground nuclear explosions that interact with the surface of the earth entrain materials from the surrounding environment, influencing the resulting physical and chemical evolution of the fireball, which can affect the final chemical phase and mobility of hazardous radionuclides that are dispersed in the environment as fallout particles. The interaction of iron with a nuclear explosion is of specific interest due to the potential for iron to act as a redox buffer and because of the likelihood of significant masses of metals to be present in urban environments. We investigated fallout from a historic surface interacting nuclear explosion conducted on a steel tower and report the discovery of widespread and diverse iron-rich micro-structures preserved within the samples, including crystalline dendrites and micron-scale iron-rich spheres with liquid immiscibility textures. We assert these micro-structures reflect local redox conditions and cooling rates and can inform interpretation of high temperature events, enabling new insights into fireball condensation physics and chemistry when metals from the local environment (i.e. structural steel) are vaporized or entrained. Finally, these observations also significantly expand the availability of silicate immiscibility datasets applicable to rapidly quenched systems such as meteorite impact melt glass.
The presentation describes the Sigma program: the mission is manufacturing science and R&D, with a long history in the nation’s weapons programs
Test bed engineering, monitoring for underground explosive and nuclear testing will be needed if the United States returns to a test posture of nuclear device testing. To maintain and rebuild the capability of test readiness, agile cost-effective test beds are needed and LANL as well as NNSS are the perfect locations to do this. Shallow and deep boreholes should be created to research containment science, diagnostic placement and optimization, coupling and emplacement science, tracer use for fracture and cratering research, and validation of test article performance.