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This presentation covers: Discovery Era: 1945-1958, Test Moratorium: 1958-1961, Testing the Limits Era: 1961-1963, Building the Stockpile Era: 1963-1992, Post Testing Era: 1992 and Beyond, Plowshare Program, Nuclear Treaties, Summary, and Questions.
What was the name of the largest and heaviest LANL weapon?
The purpose of NFO is to create a shared understanding of and appreciation for the overall weapons mission and how it is accomplished; highlight how the various roles in the Weapons Program contribute to mission success; and accelerate new employee integration.
Topics covered include: Defining Deterrence, And Why it Matters; Deterrence Today - Challenges of Great Power, Competition and Multi-Polar Nuclear Interaction; Deterrence and Our Mission -- Science underpins Deterrence; and, Questions and Answers.
Topics include: 2018 Nuclear Posture Review (NPR): Examples of Threats as Described in the NPR; Stockpile Stewardship Management Plan (SSMP); Group Project (Not Applicable in an Online Presentation Venue); References; Questions and Answers;
The presentation covers the following areas: Personnel Security; Substance Abuse Program; Physical Security; Prohibited and Controlled Articles; Information Protection & Cyber Security; Operations Security (OPSEC); Policies and Resources; and, Questions and Answers.
Topics covered include: Our Science; Guiding Principle of Los Alamos; LANL the Design Laboratory; Weapons Mission; Science, Engineering and Computations; Future Weapons Program R&D; NNSA; Aging Weapons; A Final Thought; and, Questions and Answers.
Topics covered include: ALDX Organizational Structure; Weapons Physics Mission; Assessment of the Current Stockpile; Capabilities that ALDX Stewards; U.S. Nuclear Forces; The Future Weapons Science Program; The Nuclear Threats; Some Major Technical Challenges; Final Messages; and, Questions and Answers.
The presentation topics are: Associate Laboratory Directorate for Weapons Production (ALDWP) Overview; Plutonium Center and Science; Detonators; and, ALDWP Today.
The presentation topics are: Why We are Here; Classification Office and Officials; Mission Areas with Classified Aspects; Classification Categories; Classification Policies; Unclassified and Declassified Information; Official Use Only Information; and, Unclassified Controlled Nuclear Information.
Presentation topics for the Export Control Overview are: LANL Export Control Team; Export Regulations and Responsibilities; Explaining Export Control; Weapons Program Activities Related to Export Control; Foreign Nationals and Export Control; Publications & Unlimited Release; and, Lessons Learned.
Objectives of this presentation are: 1. Explain the difference between radiation safety vs. criticality safety, 2. Define criticality, 3. Explain the three types of chain reactions, 4. Define two terms scientists use to characterize criticality, 5. Explain what occurs during a criticality accident, 6. Identify prevention measures for avoiding a criticality accident, and 7. Identify the parameters that effect criticality of a system.
Motivated by recent observations suggesting that the solar corona is heated by Alfvén wave damping at unexpectedly low heights, we performed experiments to study the basic plasma physics of Alfvén wave dissipation. Proposed coronal damping mechanisms rely on inhomogeneities in the plasma, but these theories have not been systematically studied in the laboratory. We performed experiments using the Large Plasma Device (LAPD) to test these theories.
This presentation covers the following: 1. Review of nuclear physics, 2. Fission weapons (WW2 and aftermath), 3. Weapon Effects, 4. Fusion physics, boost, and the hydrogen bomb, 5. Weapon development history – 1950’s, 6. Project Plowshare, 7. Modern weapons: the “Triad”, and 8. Thoughts on current situation and conclusions.
The electronic structure and ultrafast (10-15 s-femtosecond timescale) electron dynamics were investigated for clean and atom/molecule covered metal surfaces. The studies were performed by scanning tunneling microscopy (STM) to measure the structure of adsorbed atoms and molecules on metal surfaces, and to investigate their electronic properties. The electronic structure of the observed molecular networks was calculated by electronic structure theory in collaboration with Prof. Jin Zhao, who is a long-time collaborator, a Professor at the University of Science and Technology of China, and holds an Adjunct Professorship at the University of Pittsburgh. We also investigated the electronic properties of C60 molecules when they are templated by corrugated black phosphorous surfaces. We found unexpected charge delocalization that is enabled by the templating. This research was done in collaboration with Professor Min Feng at the Wuhan University, and who also holds an Adjunct Professorship at the University of Pittsburgh. Moreover, the electronic structure and electron dynamics in metal surfaces were investigated by time-resolved photoemission electron spectroscopy. The focus of ultrafast spectroscopy has been on the plasmonic response of silver surfaces. One direction has been to develop multidimensional (energy, momentum, and time) photoelectron spectroscopy of the coherent response of solid surfaces. This method was applied to study the collective electron excitations known generally as plasmons, which screen optical fields from penetration into metals. Although this collective response has been known for more than 60 years and is used extensively to deposit optical energy into metals, how this happens is poorly known. We investigated the plasmonic response of silver at the point where the dielectric response passes through zero and bulk plasmon is excited by light. We discovered that the plasmon excitation decays by exciting electrons from the Fermi level of a metal, which is contrary to what is believed in the plasmonic science community. This research has been performed in collaboration with Dr. Marcel Reutzel, who was a postdoctoral fellow working on this research at the University of Pittsburgh, and now has a faculty position at the University of Göttingen in Germany. Prof. Branko Gumhalter from the Institute of Physics in Zagreb contributed on the theory of plasmonic decay processes. Furthermore, we investigated the Floquet engineering of electronic bands in metals leading to multiphoton photoemission and above threshold photoemission. Finally, we demonstrated that it is possible to change the electronic structure of metals by application of optical fields. Our studies indicated that this happens on subfemtosecond time scale and could potentially be used in ultrafast information processing and quantum computation. Related document information
This presentation provides an overview of common detector concepts
The Savannah River Site (SRS) Liquid Waste System (LWS) contains approximately 66 tons of mercury within the liquids, salts, and sludges that are currently being processed into final wasteforms for disposal. Mercury concentrations within the system exceed those typically experienced in environmental or industrial systems; thus, management of mercury compounds continues to be a priority for SRS. In the LWS, waste is vitrified into a borosilicate glass wasteform that contains most of the radioactivity, while the lower activity solutions are dispositioned in a low-level grout wasteform, or “saltstone”. The alkaline, high ionic strength caustic wastes are pumped, evaporated, and otherwise managed throughout the LWS and Defense Waste Processing Facility (DWPF) as they are stored and prepared for conversion to the final wasteforms. Because of the complexity of this system, a key component of effective mercury management in the LWS requires analysis of mercury in various physical phases. The high concentration of mercury within the SRS LWS has the potential to generate vapor-phase contamination. Elemental mercury (Hg 0 ), dimethylmercury ((CH 3 ) 2 Hg), and methylmercury (CH 3 Hg + ) are among species known or suspected to contribute to the flux of mercury from liquid to vapor phase (Iverfeldt and Lindquist, 1982). Chemical speciation affects not only mercury behavior in LWS operations but may also affect the performance of mercury treatment and removal technologies in the LWS.
Zirconium (Zr) alloys are extensively used as tritium (T) getters in nuclear reactors due to their low absorption cross section to thermal neutron, good mechanical properties at high temperature and resistant to corrosion in different environmental conditions. Zr alloys have better thermal properties than many other refractory alloys including stainless steel. The nuclear characteristic is simulated, and T is produced in tritium-producing burnable absorber rods (TPBAR) by the irradiation of neutron flux in pressurized water reactor (PWR). T thus produced diffuses through the pellets and is captured by the getter where it chemically reacts with Zr to form metal hydride (ZrTx). These hydrides are brittle and affect adversely the mechanical properties of alloys. In addition to that, mismatch in the lattice structures after hydride formation creates a stress which needs to be considered in component design and their life evaluation. Therefore, understanding the behavior of T and its species becomes significant as fuel burnup is increased, which leads to increase in hydrogen pickup and oxide formation. The transport of T and its species in pure Zr alloys, and in alloys with certain alloying elements and defects are important to understand in order to enhance the performance of the materials.