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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 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

The Trinity High Explosive Implosion System: The Foundation for Precision Explosive Applications

This article is set during the 1944 and 1945 final push to complete Project Y—the Manhattan Project at Los Alamos—and focuses primarily on overcoming the challenge of creating and demonstrating a successful convergent explosive implosion to turn a subcritical quantity of plutonium into a critical mass. The critical mass would then efficiently yield kilotons of trinitrotoluene (TNT)-equivalent energy in about a microsecond, demonstrating the implosion atomic bomb concept. This work culminated in the Trinity atomic test near Alamogordo on July 16, 1945. This implosion effect demarcated the approach to explosive science and technology the Laboratory has followed ever since, including development of high-explosive synthesis and formulation, small and large test and diagnostic facilities, shock dynamics theory, high-explosive system design engineering, and three-dimensional implosion modeling and simulation using some of the fastest computers in the world. This work also ushered in a period of broader application of precision high explosives in conventional munitions, demolition, mining and oil exploration, and space travel.

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

Thirty Minutes Before the Dawn

The Trinity test of July 16, 1945, marked the scientific apex of the Manhattan Project. Often recognized as the symbolic birth of the nuclear age, Trinity’s multifaceted legacy remains just as captivating and complex today as it did 75 years ago. This paper examines why the test was necessary from a technical standpoint, shows how Los Alamos scientists planned the event, and explores the physical and emotional aftermaths of Trinity. The author also uses rarely accessed original records to reconstruct the story of Trinity’s health hazards, as seen through the eyes of radiation technicians and medical doctors as events unfolded. Trinity was conducted as the Potsdam Conference began, weeks after the collapse of Nazi Germany. It was considered necessary to let President Harry S. Truman know whether the United States possessed a nuclear capability ahead of his negotiations with Joseph Stalin, the Soviet premier. The author examines the competing priorities that drove the timetable for the test: international politics, security, and safety. Three weeks after Trinity, a gun-assembled enriched-uranium bomb called Little Boy was used against the Japanese city of Hiroshima. Three days later, Fat Man, a weaponized version of the imploding Trinity device, was dropped on Nagasaki. The author briefly examines these strikes and what impact they may have had on the Japanese surrender. The paper concludes by examining the legacy of the Trinity test 75 years into the age it helped usher in.

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

Listen: Oppenheimer’s office chair one of the only possessions the lab has from our first director

Even the father of the atomic bomb had to sit down somewhere. It's hard to believe that our legendary first Lab director and brilliant physicist J. Robert Oppenheimer did something as ordinary as using a chair at work like the rest of us do. However, aside from a recently gifted book, this chair from the 1940s is the only Oppenheimer possession that the Lab has. And Oppie fans love it. The chair is routinely loaned to museums nationwide for display.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2021

Radiochemistry and Trinity

Forty seconds after Trinity detonated, Noble Laureate Enrico Fermi calculated the bomb’s energy release. By measuring the lateral dispersion of small pieces of paper dropped before, during, and after the blast wave passed him, he calculated an explosive yield of ten kilotons. Although Fermi’s estimate was only half of the official yield, it provided immediate confirmation that nuclear fission could be fashioned into a weapon of war.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2020

Sulfur Pellets Responses to a Bare and Steel Reflected Pulse of the Oak Ridge National Laboratory Health Physics Research Reactor

The experiments analyzed in this report were conducted at the Health Physics Research Reactor (HPRR), also known as the $\textit{Fast Burst Reactor}$. The reactor was designed and built at Oak Ridge National Laboratory (ORNL) in 1961. The HPRR was an unmoderated, unshielded fast reactor that used highly enriched uranium and molybdenum alloy as fuel. The reactor was initially sent to the Nevada Test Site in 1962, where it was used to evaluate radiation doses received as a result of the Hiroshima and Nagasaki bombings during World War II. A few years later, the reactor was sent back to ORNL to be part of the Dosimetry Application Research (DOSAR) facility shown in Figure 1, which included a reactor building shown on the left (west) of the picture and a control and laboratory building in the upper right corner (northeast). The critical assembly was used for numerous technical studies, including systems calibration, dosimetry, radiobiology of plants and animals, testing of radiation alarms, as well as teaching and training in radiation dosimetry and nuclear engineering. Between 1963 and 1987, the HPRR was operated for thousands of hours, achieving criticality close to 10,000 times and motivating many publications. The HPRR was decommissioned in 1987. The goal of this effort was to use historical data from operation of the HPRR to create a criticality accident alarm system (CAAS) benchmark to be included in the $\textit{International Handbook of Evaluated Criticality Safety Benchmark Experiments}$ (ICSBEP Handbook). A thorough inspection was performed of all available documentation and information available. The most promising experiments that were selected for evaluation were those described in the 1987 ORNL report entitled $\textit{Health Physics Research Reactor Reference Dosimetry}$, ORNL-6240. The report includes reference dosimetry results of the shielded and unshielded configurations of the HPRR after burst operations. Because of changes to the reactor positioning and storage systems that were made in 1985, the previous dosimetry reports became obsolete, and the newly designed experiments were needed to create the HPRR’s adjusted dosimetry data. The various results reported in ORNL-6240 include reference doses and dose equivalents from different conventions at different distances and elevations as determined using the detected neutron fluence and conversion factors. The HPRR neutron fluence was obtained through different methods, including sulfur pellet analysis and threshold detector unit data. Information about the HPRR spectrum was also obtained through Bonner sphere measurements. This benchmark is focused on a part of the measured sulfur fluences reported in Appendix H of ORNL-6240. Standard commercial sulfur pellets were placed at different distances from the HPRR centerline during burst operation and were activated due to the 32 S(n,p) 32 P reaction. The resulting 32 P activity was then measured and the information about the corresponding sulfur fluence and/or neutron dose could be extracted. Many of those measurements have 7 been performed with the HPRR in its bare configuration or with different shields (combinations of Lucite, concrete, steel). All the necessary, precise information about material and/or dimensions of the different shields was not found, so it was decided to focus only on the unshielded and steel-shielded configurations to minimize the benchmark uncertainty. A total of 31 cases (24 unshielded and 7 shielded cases at different positions) of sulfur fluence were selected before evaluation to develop the benchmark.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2021

Harold Agnew’s son gives Lab never-before-seen photos, documents

When I arrived at Los Alamos in 2003, the Laboratory’s long-retired third director was still a very popular figure. He was so popular, in fact, that he enjoyed an honor typically reserved for only the most adored and outrageous pop stars and Brazilian footballers: He was known by one name. Back then, most Lab staff knew exactly who you were talking about when you referred to “Harold.” Harold Agnew was at the helm from 1970 – 1979, though his career here began when he was still just in his 20s. He was recruited to work on the U.S. government’s top-secret project to build the first atomic bombs and help bring a swift end to World War II. Harold died in 2013 at 92, but March 28 would have been his 100th birthday. Although he’s no longer here to celebrate with us, we can gain inspiration by remembering his remarkable life of service – and mischief. Both are now well-documented in the collections of the National Security Research Center (NSRC), the Lab’s classified library, which also includes unclassified pieces of our history. The NSRC’s newest addition to its collections comes from Harold’s son John Agnew, who just recently gave me a box of about 250 images and about 15 documents that belonged to his dad. The contents are nothing short of remarkable, one-of-a-kind, and in some cases, hilarious. As the NSRC staff are accessioning these pieces into the Lab’s collections, looking through these materials is a chance for me to remember our former director and my friend.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2021

A Father’s Day Tribute Father-son Nobel Prize-winning physicists worked together at the Lab

Partners in physics during the World War II years, father and son Niels and Aage Bohr worked side by side on the Lab’s top-secret effort to create the first atomic bombs. Arriving in Los Alamos in late 1943, Aage was just 21 years old. He had been studying physics to follow in the footsteps of his father, who had won a Nobel Prize in 1922. Aage’s higher education, however, had been interrupted by the rapid spread of Nazism in Europe. The Bohrs, who had Jewish heritage, fled their native Denmark to escape persecution, eventually arriving in Los Alamos to aid in the creation of weapons that would help end the war. Their story is part of the collections at the National Security Research Center, which is the Lab’s classified library and also houses unclassified historic materials. While at Los Alamos, Niels and Aage were accorded VIP status because of the family’s scientific renown and given new names to protect their identities: Aage was James Baker, while his father was Nicholas Baker, but the scientific community called him Uncle Nick. Whether called Niels and Aage or Nick and Jim, father and son were inseparable.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2021

Commuting again to work on-site? Lab’s first drivers faced their own challenges decades ago

After a long pause in commuting, more and more Lab staff are filling travel mugs, topping off their tanks, and heading up the hill for on-site work. As long as the Lab has existed, workers have snaked through tight mountain roads to get to their jobs. And, back in the early 1940s, drivers faced even more challenges. In the Lab’s earliest years, drivers likely worried about getting stuck in the mud, navigating intense switchbacks, or making sure important equipment, such as a disassembled power plant, didn’t fall off the back of the truck that was hauling it. Creative solutions could go a long way to get out of a jam. As many of us return onsite and get reacquainted with commuting, we look back at how transportation has changed since the Manhattan Project, the U.S. government’s top secret effort at Los Alamos to create the first atomic bombs to help end World War II. These stories and photos are part of the collections in the National Security Research Center, which is the Lab’s classified library and also houses unclassified artifacts from our past.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2021

Winning Asset Management Improvement Team: Maintenance Planning and Scheduling in a Highly Regulated Environment

The Y-12 National Complex (Y-12) site has numerous aging facilities that are crucial to the Department of Energy and the national security strategy for the nation. Y-12’s commitment to safety and regulatory compliance is of the highest importance. The commitment to meet the national security mission also creates additional rigor and complexity to the everyday maintenance and planning process. Y-12 is a collection of many facilities, both old and new, nestled between two ridges in Oak Ridge, TN. Y-12 was made with the short-term focus of ending “The Great War” through the creation of the worlds’ first atomic bomb. Almost eighty (80) years have passed since the groundbreaking, with the mission of the site changing from decade to decade. While the mission has changed, the way Y-12 employees continuously meet the challenge has not. The site was created to react and overcome; Y-12 still takes pride in the ability to react and overcome. The difference is the site is no longer ignorant to the need for a better way to manage the aging facilities and infrastructure. Shear willpower and determination was once the way to reach the objectives, but as a wise man once said, “Work smarter, not harder.” The business case for change started within the senior leadership at Y-12. A team of managers sat down and dictated objectives to provide a clear scope for the maintenance planning and scheduling optimization team, to include our Eruditio integrated blended learning coaches. In addition to providing the direction, they also made themselves available for escalation of issues in the event the team ran in to road blocks.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2021

Be like Oppenheimer: Donate your weapons information for the next generation of LANL researchers

You can follow the Lab’s first physicists, J. Robert Oppenheimer, Richard Feynman, Hans Bethe, and so many others through the years, plus know your information is helping future researchers — just like our first scientists did for you. How? Donate your physical or digital classified weapons records to the Lab’s National Security Research Center (NSRC), said Riz Ali, NSRC Director. The NSRC houses 80 years’ worth of one-of-kind records, which total in the millions and include nearly every medium imaginable. It is the Laboratory’s largest collection of research materials and the largest classified library of any Department of Energy lab. It all started with Oppenheimer, our first Lab director, and his Technical Library that was established during the Manhattan Project, which was the U.S. government’s top-secret effort to create the first atomic bombs to help end World War II. “Few NSRC patrons are aware that most of its vital materials come from the Lab’s own workforce,” said Chris C’de Baca, the NSRC’s Group Leader. “A significant portion of our critical material — which today’s researchers access regularly — is a direct contribution from research scientists. If people don’t contribute, then we won’t have the information we need when people come to the NSRC for research.”

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2021

Phosgene Neutralization Chemistry for the Explosive Destruction System (EDS)

This report summarizes activities at Sandia National Laboratories as part of the Explosive Destruction System (EDS) Phase 3 (P3) System design. An exploration of chemical neutralization strategies of phosgene was conducted for safe disposal of recovered mortars and M79 1000 lb. bombs filled with carbonyl dichloride "phosgene" or "CG agent" (molecular formula = COCl 2 ). The incumbent strategy utilized aqueous sodium hydroxide was found to be the worst-case scenario, producing enough CO 2 gas that would cause an unacceptable pressure and temperature spike. Several chemical neutralization strategies were evaluated based on criteria set by the operating envelope of the P3 design. In the end, it was determined that a pure solution of N-methyl ethanolamine (MeEA) or 90% monoethanolamine (MEA)(aqueous) provided the best balance reaction profile, cost, and safety.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Ranger

On January 11, 1951, the Atomic Energy Commission announced that the President of the United States had authorized the Commission to use part of Las Vegas Bombing and Gunnery Range for “experiments necessary to the atomic weapons development program.” Sixteen days later, on January 21st, the first test, codenamed Able, exploded at 0545 hours Pacific Standard Time 1,060 feet over the dry lake bed of Frenchman Flat with a yield of one kiloton. In quick succession, four more devices were dropped over Frenchman Flat with yields ranging from one to twenty-two kilotons.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2021

Operation Ivy

Operation Ivy, a two-shot test program, included the United States’ first thermonuclear device, Mike; and King, its highest yield fission bomb. Mike, if successful, held the promise of future weapons having megaton yields. King, pushing the limits of a fission design, provided a high yield alternative should Mike fail.

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

Why didn’t Oppenheimer ever win a Nobel Prize?

For his scientific achievement, he would be forever known as the father of the atomic bomb – but never as a Nobel laureate. The pinnacle of global recognition, the Nobel Prize was bestowed on 18 of J. Robert Oppenheimer’s colleagues with whom he worked at the Manhattan Project site in Los Alamos. There, in just 27 months and in a perceived race with Nazi Germany, the scientists created the first nuclear weapons. Their efforts brought the world into the Atomic Age and helped end World War II. Several were awarded the prize before coming to work at the wartime lab, while most would go on to win later in life. Oppenheimer was nominated for the Nobel Prize for Physics three times: in 1946, in 1951, and in 1967. Colleagues, scholars, and surely Oppenheimer himself pondered why he was never bestowed the honor. “To understand this,” said James Kunetka, historian and author of The General and the Genius, “you have to first examine the man’s academic life before and after the war.”

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2021

Lab’s original mission inspires entire genre of comic books, characters

The Lab’s advent of the atomic bomb that helped end World War II in 1945 fueled the imagination of comic book writers. The public’s focus on emerging nuclear science made the idea of people-turned-super through radiation wildly popular in many aspects of pop culture.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2021

Physical Lab Security: Before and After World War II

Physical security during World War II was important to maintaining the secrecy of the Manhattan Project, the government’s wartime effort to create the atomic bomb. In a perceived race against Nazi Germany to do so, physicist J. Robert Oppenheimer, the Lab’s first director, and General Leslie Groves, head of the Manhattan Project, needed a secluded place to build the clandestine Lab.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2021

Chicago Pile-1 paved the way for nuclear science and a lab in Los Alamos First self-sustaining nuclear chain reaction was nearly 80 years ago

On a bitter-cold winter day, 43 scientists gathered at an abandoned squash court at the University of Chicago where they would ultimately enable a secret lab in Los Alamos to change the world just years later. It was December 2, 1942. The group, led by Italian physicist and Nobel laureate Enrico Fermi, stacked graphite bricks, piling 57 layers that totaled more than 770,000 pounds. Later named Chicago Pile-1, their goal was to create the world’s first self-sustaining, controlled nuclear chain reaction. Inside the approximately 20-feet-tall pile were smaller blocks of uranium and control rods that, when removed, would cause the reaction to go critical – meaning create a nuclear chain reaction. It was roughly $1 million worth of materials, equivalent to nearly $16 million today, and a concept that a nuclear chain reaction would allow the weaponization of the atom. “Its success would be the crucial proof needed to know it would be possible to create an atomic bomb,” said LANL Historian Roger Meade (C-NR). “This was the precursor to the Lab we have today, nearly 80 years later.”

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗