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Glaser, Alexander

Publications and source records attributed to Glaser, Alexander.

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Remote inspection of adversary-controlled environments

Remotely monitoring the location and enduring presence of valuable items in adversary-controlled environments presents significant challenges. In this article, we demonstrate a monitoring approach that leverages the gigahertz radio-wave scattering and absorption of a room and its contents, including a set of mirrors with random orientations placed inside, to remotely verify the absence of any disturbance over time. Our technique extends to large physical systems the application of physical unclonable functions for integrity protection. Its main applications are scenarios where parties are mutually distrustful and have privacy and security constraints. Examples range from the verification of nuclear arms-control treaties to the securing of currency, artwork, or data centers.

47 OTHER INSTRUMENTATION↗
DOE OSTI2023

Ceci N’est Pas Une Bombe: Lessons from a Field Experiment Using Neutron and Gamma Measurements to Confirm the Absence of Nuclear Weapons

In March 2023, the UN Institute for Disarmament Research held a verification experiment that included a mockup onsite inspection at a former military facility in the municipality of Menzingen, Switzerland. The experiment included a visit to the site by an inspection team, accompanied by the host team. Among other activities, radiation measurements were used to confirm the non-nuclear nature of selected items stored onsite. In this paper, we discuss the neutron and gamma measurement systems used during the experiment and the inspection protocols followed to confirm the absence of nuclear weapons. Furthermore, results from the experiment and a laboratory reproduction are presented, before concluding with lessons learned for how absence-confirmation measurements can help support verification of future arms control agreements.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2022

Experimental demonstration and modeling of a robotic neutron detector with spectral and directional sensitivity for treaty verification

International safeguards and arms control agreements often require labor-intensive, intrusive onsite inspections to perform verification tasks. The ability to localize a neutron source and/or characterize a neutron field may be imperative for identifying anomalies. We are interested in the role of autonomous mobile robots, which, if designed properly, may be more effective and efficient and less intrusive than their human counterparts. Toward developing such a capability, we, for this study, have constructed the N-SpecDir Bot, comprised of three boron-coated straw detectors azimuthally-distributed within a cylinder of high-density polyethylene, which is mounted on an omni-directional robotic platform. Our N-SpecDir Bot is specifically designed to provide spectral and directional sensitivity, in addition to gross counts, by utilizing the signals from the three detectors. The detection system has been extensively characterized by MCNP modeling, which has been benchmarked to experiments conducted at the Princeton Plasma Physics Laboratory. We demonstrate the spectral and directional sensitivity experimentally and in simulation, and provide a simple yet robust method for directional measurements.

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

Confirming the absence of nuclear warheads via passive gamma-ray measurements

Arms-control agreements between the United States and Russia negotiated after the end of the Cold War have imposed limits on the number of deployed strategic nuclear weapons. Verification of these agreements has relied on onsite inspections, sometimes supported by radiation detection techniques to confirm the absence of a nuclear warhead when ambiguities arise. So far, these measurements have sought to detect neutron emissions associated with the presence of plutonium, but they would be inadequate for uranium devices. In an effort to offer instruments that could be used to confirm the absence of both plutonium and uranium weapons, here we propose an inspection system that uses only passive gamma radiation detection techniques. Such a system would be particularly valuable for next-generation arms-control agreements that limit total numbers of weapons and would involve containerized items in storage. We conducted extensive Monte Carlo simulations to support the development of a verification protocol and detection algorithm. Here, we demonstrate the viability of the technique using standard laboratory check sources and MCNP simulations for simplified configurations of special nuclear material.

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

Verifying Deep Reductions in the Nuclear Arsenals: Development and Demonstration of a Motion-detection Subsystem for a “Buddy Tag” Using Non-export Controlled Accelerometers

Future nuclear arms-control agreements may place numerical limits on items that are difficult to monitor with national technical means, even when complemented with onsite inspections. Such items could include small objects and mobile assets, such as non-deployed nuclear warheads and mobile missile launchers. Typically, this verification task can be addressed with unique identifiers, but standard tagging techniques may be unacceptable in this case due to host concerns about safety and intrusiveness. First proposed in the late 1980s and partially developed by Sandia National Laboratories in the early 1990s, the “Proximity Tag” or “Buddy Tag” concept seeks to overcome these concerns by separating the tag from the treaty accountable item itself. A buddy tag has two key elements: a tamper-indicating enclosure and a motion-detection system designed to detect illicit movements in a stand-down period. As part of this project, we have built a buddy-tag prototype for demonstration and evaluation purposes. This paper reviews the design choices and functionalities of the tag’s motion-detection subsystem.We pursue a modular approach for the tag’s hardware, built around an Arduino-class microcontroller and a non-export-controlled low-noise accelerometer, and use open-source algorithms for the motion-detection software. Finally, we discuss the results of an extensive experimental campaign involving both indoor and outdoor measurements assessing the performance of the tag under real-world environmental conditions.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2019

Vintage electronics for trusted radiation measurements and verified dismantlement of nuclear weapons

Information barriers are trusted measurement systems to confirm the authenticity of nuclear warheads based on their radiation signatures. Traditional inspection systems rely on complex electronics both for data acquisition and processing. Several research efforts have produced prototype systems, but it has proven difficult to demonstrate that hidden switches and side channels do not exist. After almost thirty years of research and development, no viable and widely accepted system has emerged. We pursue a fundamentally different approach: Our prototype of an inspection system uses vintage hardware built around a 6502 processor. The processor uses 8-micron technology and has only about 4,200 transistors. Vintage electronics may have a number of important advantages for applications where two parties need to simultaneously establish trust in the hardware used. CPUs designed in the distant past, at a time when their use for sensitive measurements was never envisioned, drastically reduce concerns that the other party implemented backdoors or hidden switches on the hardware level. We demonstrate the performance of a prototype system using an Apple IIe and a custom-made open-source data-processing board connected to a standard sodiumiodide radiation detector for low-resolution gamma spectroscopy. Data processing and analysis is exclusively done on the Apple IIe hardware. We show that subtle differences in radiation signatures can be detected in 2–3 minutes based on the result of a simple chi-squared test. Vintage electronics may therefore offer a new path toward fieldable, trusted information barriers.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2019

Deferred Verification: The Role of New Verification Technologies and Approaches

Researchers at UNIDIR have recently proposed a fundamentally new approach to nuclear arms control verification, dubbed "deferred verification." The concept forgoes inspections at sensitive nuclear sites and inspections of nuclear materials or components in classified form. To implement this concept, a state first divides its territory into a closed segment and an open segment. The total fissile material inventory in the closed segment, which includes the weapon complex, is known and declared with very high accuracy. Essentially no inspections take place in the closed segment. Yet, inspectors have access to the open segment, which includes in particular the civilian nuclear sector. The fissile material inventory in the open segment is known with less accuracy, but uncertainties can be reduced over time using methods of nuclear archaeology. Deferred verification relies primarily on established safeguards techniques and avoids many unresolved verification challenges, including for example the need for information barriers for warhead confirmation measurements. At the same time, deferred verification faces some unique challenges. In this work, we explore some of these challenges and offer possible solutions while maintaining the strengths of the concept; to do so, we examine possible noncompliance strategies in which a state would seek to withhold a higher-than-declared inventory.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2019

A Cryptographic Escrow for Treaty Declarations and Step-by-Step Verification

The verification of arms-control and disarmament agreements requires states to provide declarations, including information on sensitive military sites and assets. There are important cases, however, where negotiations of these agreements are impeded because states are reluctant to provide any such data, because of concerns about prematurely handing over militarily significant information. To address this challenge, we present a cryptographic escrow that allows a state to make a complete declaration of sites and assets at the outset and commit to its content, but only reveal the sensitive information therein sequentially. Combined with an inspection regime, our escrow allows for step-by-step verification of the correctness and completeness of the initial declaration so that the information release and inspections keep pace with parallel diplomatic and political processes. We apply this approach to the possible denuclearization of North Korea. Such approaches can be applied, however, to any agreement requiring the sharing of sensitive information.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2019

Nuclear Archaeology to Distinguish Plutonium and Tritium Production Modes in Heavy-Water Reactors

Several nuclear archaeology techniques have been proposed to determine historic plutonium production in dedicated nuclear reactors. These methods rely on sampling materials from the reactor core or specially designed monitor tags, to examine suited isotopic ratios and deduce the amount of plutonium produced. However, some production reactors can be used to produce other isotopes than plutonium, such as tritium. If a reactor has been declared to produce tritium, it could be crucial to confirm that this was the case and that the reactor was not used to produce plutonium instead. In this paper, we describe how isotopic ratios discrepancies can be used to distinguish between plutonium and tritium production modes. Here, we present results obtained via the simulation of reactor lattices inspired by Savannah River Site heavy water production reactors and show that elements such as hafnium and tungsten can be conveniently used to detect undeclared production of plutonium.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2018

Denuclearizing North Korea: A verified, phased approach

At the Singapore Summit of 12 June 2018, for the third time, the leaders of the United States and the Democratic People’s Republic of Korea (DPRK) agreed to seek a diplomatic resolution to the decades of conflict between their two nations. At the Summit, “President Trump committed to provide security guarantees to the DPRK, and Chairman Kim Jong Un reaffirmed his firm and unwavering commitment to complete denuclearization of the Korean Peninsula.”1 Achieving the denuclearization of the Korean Peninsula will involve solving difficult and entangled technical and policy questions of how to verify nuclear disarmament. The outcome will shape how the international community approaches this task for the other eight states that currently have nuclear weapons.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2017

Minimally Intrusive Verification of Deep Nuclear Warhead Reductions: A Fresh Look at the Buddy-Tag Concept

Future nuclear arms - control agreements may place numerical limits on the total number of warheads in the nuclear arsenals of states. Verifying these limits may require inspectors to account for individual warheads, both deployed and non-deployed. This task could be accomplished with unique identifiers, but standard tagging techniques may be unacceptable in this case due to host concerns about safety and intrusiveness. To resolve this dilemma, we revisit the so - called Buddy Tag concept first proposed by Sandia National Laboratories in the early 1990s. The conceptual innovation in the Buddy Tag was to by separate the tag from the treaty limited item itself. Verification of the pairings between tags and limited items would take place during a short-notice inspection, where the host would be required to produce one buddy tag for each item. Sensors on the Buddy Tag would show that it had not been moved to the inspected site after the inspection was declared (e.g., within the last 24-48 hours). If the inspector counted more (or fewer) treaty limited items than Buddy Tags at the inspected site, a treaty violation could be asserted. Using a number of single-site inspections, an inspecting party can hold the host at risk for discovery of violating the treaty at an enterprise level by possessing more treaty limited items than the treaty allows. In this project, we developed a buddy-tag prototype for demonstration and evaluation purposes. This paper summarizes the performance requirements for an advanced Buddy Tag, the proposed conduct of operations, the design choices and functionalities of the different subsystems, and initial testing results. The report also summarizes peer review feedback obtained throughout the project.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2017

Information barrier experimental: Toward a trusted and open-source computing platform for nuclear warhead verification

Trusted measurement systems are critical for the verification of future arms-control treaties that involve confirming the authenticity of nuclear warheads on the basis of their radiation signatures. Several research efforts have produced prototype systems, but their designs are typically not published in detail, making it difficult to enable trust in these devices. The Information Barrier Experimental (IBX) is a new prototype built around the Red Pitaya computing platform using passive gamma spectroscopy. It is the first such platform designed to help a broad research community study vulnerabilities and define the required specifications for a common, trusted inspection system. It is low-cost, simple to assemble, and enables comprehensive hardware and software authentication studies. The device follows a digital data acquisition approach, which significantly reduces the number of components between scintillator and spectrum output. Finally, measurements demonstrate that this approach is technically feasible and produces excellent measurement results.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2017

Fissile Material Stockpile Declarations and Cooperative Nuclear Archaeology

With the beginning of the Cold War, the United States and the Soviet Union quickly began to produce fissile material (plutonium and highly enriched uranium, HEU) for military purposes on an industrial scale. By the mid-1950s, both countries were already making ton-quantities of fissile material per year to supply their growing nuclear arsenals. They were soon joined by the United Kingdom (1951), France (1955), China (1964), and Israel (1965)—and later by India, Pakistan, and finally North Korea. By the time most of these production efforts ended in the early 1990s, the global stockpile of military fissile material had reached fantastic levels. While the combined global nuclear weapon inventory had peaked at about 64,000 in 1986,1 the military fissile-material stockpile ultimately reached almost 2200 tons (240 tons of plutonium and 1960 tons of highly enriched uranium), which is sufficient to make about 200,000 simple nuclear weapons.2 Since the end of the Cold War, almost 700 tons of highly enriched uranium have been down-blended and other material is now reserved for naval fuel. Overall, the military material available for weapon purposes today is sufficient for more than 150,000 weapons (Figure 1).

Glaser, Alexander↗
DOE OSTI2016

Low-resolution gamma-ray spectrometry for an information barrier based on a multi-criteria template-matching approach

Gamma-ray spectrometry has been successfully employed to identify unique items containing special nuclear materials. Template information barriers have been developed in the past to confirm items as warheads by comparing their gamma signature to the signature of true warheads. Their development has, however, not been fully transparent, and they may not be sensitive to some relevant evasion scenarios. Here, we develop a fully open template information barrier concept, based on low-resolution measurements, which, by design, reduces the extent of revealed sensitive information. The concept is based on three signatures of an item to be compared to a recorded template. The similarity of the spectrum is assessed by a modification of the Kolmogorov–Smirnov test to confirm the isotopic composition. The total gamma count rate must agree with the template as a measure of the projected surface of the object. In order to detect the diversion of fissile material from the interior of an item, a polyethylene mask is placed in front of the detector. Neutrons from spontaneous and induced fission events in the item produce 2.223 MeV gamma rays from neutron capture by hydrogen-1 in the mask. This peak is detected and its intensity scales with the item's fissile mass. This analysis is based on MCNP Monte Carlo simulations of various plutonium configurations suggests that this concept can distinguish a valid item from a variety of invalid ones. The concept intentionally avoids any assumptions about specific spectral features, such as looking for specific gamma peaks of specific isotopes, thereby facilitating a fully unclassified discussion. Finally, by making all aspects public and allowing interested participants to contribute to the development and benchmarking, we enable a more open and inclusive discourse on this matter.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2016

A physical zero-knowledge object-comparison system for nuclear warhead verification

Zero-knowledge proofs are mathematical cryptographic methods to demonstrate the validity of a claim while providing no further information beyond the claim itself. The possibility of using such proofs to process classified and other sensitive physical data has attracted attention, especially in the field of nuclear arms control. Here we demonstrate a non-electronic fast neutron differential radiography technique using superheated emulsion detectors that can confirm that two objects are identical without revealing their geometry or composition. Such a technique could form the basis of a verification system that could confirm the authenticity of nuclear weapons without sharing any secret design information. More broadly, by demonstrating a physical zero-knowledge proof that can compare physical properties of objects, this experiment opens the door to developing other such secure proof-systems for other applications.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2016

The Virtues of Nuclear Ignorance

Americans of a certain age are well acquainted with one of Ronald Reagan’s pithier maxims: “Trust, but verify.” It is a translation of a Russian proverb, and Reagan used it often in his dealings with the Soviet Union over nuclear disarmament, as both countries chipped away tentatively at their Cold War stockpiles. For him, the saying encapsulated the idea that a good treaty would require rigorous inspections, to insure that neither side was dragging its feet or, worse, disposing of decoy bombs, rather than real ones. But how should the process of verification work? If a U.S. scientist were allowed to dismantle a Russian warhead personally, he or she could identify it as legitimate fairly easily, even if it differed in design from American models. But, in doing so, the scientist would necessarily learn many classified details about the weapon, something that the Russians would never consent to. (Nor would the Americans, if their roles were swapped.)

29 ENERGY PLANNING, POLICY, AND ECONOMY↗