Fission Bomb Research Articles

Remarks on the yield of fission bombs

Remarks on the yield of fission bombs

Estimating North Korea's nuclear capabilities: Insights from a study on tritium production in a 5MWe graphite-moderated reactor

This study explores the potential for tritium production in North Korea's 5MWe graphite-moderated reactor, a facility primarily associated with nuclear weapons material production. While existing research on these reactors has largely centered on plutonium, our focus shifts to tritium, a crucial element in boosted fission bombs. Utilizing the MCNP6 code for simulations, the results estimate that North Korea can possibly produce approximately 7–12 g of tritium annually. This translates to the potential production of 1–3 boosted fission bombs each year. By incorporating tritium production into assessments of North Korea's nuclear capabilities, our methodology provides insights into the dynamics of the country's nuclear force, revealing a more diversified and complex composition than previously assumed. The findings significantly aid policymakers, regulatory bodies, and researchers in comprehending potential proliferation risks associated with graphite-moderated reactors and in developing strategies to address the nuclear threat emanating from North Korea.

Nuclear Fission or Fusion on Meeting Electricity Demand of Future Energy Source Economy and Policy

The announcement of the United States Department of Energy (DOE) on Tuesday, December 13, 2022 was a monumental milestone in nuclear Fusion research, where a “net energy gain driven by Inertia Fusion Confinement (ICF)” eventually, after almost 40 years of scientific efforts achieved for the first time in history by scientists from the Lawrence Livermore National Laboratory (LLNL) in California through its National Ignition Factify (NIF) program. For a long time since aftermath of “Manhattan Project”, scientists knew and had some clear concept of bringing sun energy to earth by means of “Fusion” process either via Magnetic Fusion Confinement (MFC)or ICF after their success of exploding their nuclear fission bomb through Nevada Test Site (NTS) via “Fission” process. Announcement of such an achievement by simply put it is one of the most impressive scientific feats of the 21st century as “Jennifer Granholm, secretary of U.S. Department of Energy said at a press conference. Such success puts production of electricity from nuclear energy of fusion puts it in different perspectives and it shows that researchers have been working on this for decades alongside of MCF and their efforts behind nuclear fission of Generation - IV (GEN-IV) reactors technology and manufacturing. In this short review paper, we describe all these issues of the differences between Fission and Fusion and each aspect of them being source of generating electricity to meet national and global demand for the source of it from nuclear point of view and not going to detail of renewable source of energy at this point.

The Essential Writings of Vannevar Bush edited by G. Pascal Zachary

<i>The Essential Writings of Vannevar Bush</i> edited by G. Pascal Zachary

Restricted Data: The History of Nuclear Secrecy in the United States

Restricted Data: The History of Nuclear Secrecy in the United States

Scientists under Surveillance: The FBI Files

Scientists under Surveillance: The FBI Files

Preparative scale mass spectrometry: A brief history of the calutron.

Calutrons were developed in the laboratory of E. O. Lawrence at the University of California at Berkeley. They were a modification of the cyclotrons he had invented and used in his Nobel Prize-winning investigations of the atomic nucleus. At the time their construction was undertaken, calutrons represented the only certain means of preparing enriched uranium isotopes for the construction of a fission bomb. The effort was successful enough that every atom of the 42 kg of 235 U used in the first uranium bomb had passed through at least one stage of calutron separation. At peak production, the first stage separators, α tanks, yielded an aggregate 258-g/day 235 U enriched to about 10 at. % from its natural abundance level of 0.72 at. %. The second stage separators, β tanks, used the 10 at. % material as feedstock and produced a total 204-g/day 235 U enriched to at least 80 at. %. The latter, weapons grade, material was used in fission bombs. Under typical operating conditions, each α tank operated at a uranium beam intensity at the collectors of approximately 20 mA and each β tank at a beam intensity of approximately 215 mA at the collectors. Bulk separation of isotopes for bomb production ceased in 1945. Since that time calutrons have been used to separate stable isotopes, but on a more limited scale than wartime weapons production. Stable isotope separations since 1960 have taken place using one modified β tank.

Composite cores and tamper yield: Lesser-known aspects of Manhattan Project fission bombs

This paper examines the physics of two lesser-known aspects of the nuclear weapons produced in the Manhattan Project: The idea of constructing weapons with so-called composite cores (that is, ones which would have comprised combinations of uranium and plutonium), and the fact that some 30% of the plutonium-fueled Fat Man yield was due to fissions in the uranium-238 tamper of that weapon, fissions induced by high-energy neutrons liberated by fissions in the plutonium core. Simple models of both issues give results in reasonable accord with available data.

Experimenting in the Unknown: Lessons from The Manhattan Project

Experimentation is paramount to innovation. In fact, innovation scholars and practitioners have espoused Thomke's (2003) book titled Experimentation matters: Unlocking the potential of new technologies for innovation. Unfortunately, companies still experience considerable technical and managerial difficulties with organizing experiments under high uncertainty. This study confronts Thomke's experimentation principles with a high uncertainty context by examining experiments conducted by The Manhattan Project from 1943–1945, the initiative that created the first implosion‐type fission bomb. Findings suggest that lack of theoretical knowledge, a crisis of scientific instruments, and absence of pre‐established organizations were critical to such highly uncertain experimentation. We conclude with a discussion of the boundary conditions of Thomke's experimentation principles. Finally, we propose five principles for facilitating the management of experimentation in the unknown.

A toy model for the yield of a tamped fission bomb

A simple expression is developed for estimating the yield of a tamped fission bomb, that is, a basic nuclear weapon comprising a fissile core jacketed by a surrounding neutron-reflecting tamper. This expression is based on modeling the nuclear chain reaction as a geometric progression in combination with a previously published expression for the threshold-criticality condition for such a core. The derivation is especially straightforward, as it requires no knowledge of diffusion theory and should be accessible to students of both physics and policy. The calculation can be set up as a single page spreadsheet. Application to the Little Boy and Fat Man bombs of World War II gives results in reasonable accord with published yield estimates for these weapons.

Note on the minimum critical mass for a tamped fission bomb core

An approximate but sensibly accurate formula is developed for estimating the minimum possible critical radius for a sphere of fissile material surrounded by a thick tamper of material of neutron transport mean free path λtamp. The minimum critical radius is approximately proportional to λtamp0.4; results are given for uranium-235 and plutonium-239 cores surrounded by several commonly used tamper materials.

Thermonuclear Operation Space Lift

The “Project Orion” small fission bomb propulsion concept proposed the one-stage launching of large payloads into low Earth orbit, but it was abandoned because of the radioactive fallout into Earth’s atmosphere. The idea is here revived by the replacement of the small fission bombs with pure deuterium–tritium fusion bombs, and the pusher plate of Project Orion with a large magnetic mirror. The ignition of the thermonuclear fusion reaction is done by the transient formation of keV super-explosives under the high pressure of a convergent shock wave launched into liquid hydrogen propellant by a conventional high explosive.

To Mars in Weeks by Thermonuclear Microbomb Propulsion

To reduce the radiation hazard for manned missions to Mars and beyond, a high-specific-impulse–high-thrust system is needed, with a nuclear bomb propulsion system the preferred candidate. The propulsion with small fission bombs is excluded because the critical mass requirement leads to extravagant small fission burnup rates. This leaves open the propulsion with nonfission ignited thermonuclear microexplosions, with a compact fusion microexplosion igniter (driver) and no large radiator. It should not depend on the rare isotope and only requires a small amount of tritium. This excludes lasers for ignition. With megaamperes of gigavolt proton beams and a small amount of tritium, cylindrical deuterium targets can be ignited. The proton beams are generated by discharging the entire spacecraft as a magnetically insulated gigavolt capacitor. To avoid a large radiator, needed to remove the heat from the absorption of the fast neutrons in the spacecraft, the microexplosion is surrounded by a thick layer of liquid hydrogen, stopping the neutrons and heating the hydrogen to a temperature of , which as a fully ionized plasma can be repelled from the spacecraft by a magnetic mirror.

Cold War Dixie: Militarization and Modernization in the American South by Kari Frederickson (review)

Reviewed by: Cold War Dixie: Militarization and Modernization in the American South by Kari Frederickson Andrew H. Myers (bio) Cold War Dixie: Militarization and Modernization in the American South. By Kari Frederickson. (Athens: University of Georgia Press, 2013. Pp. xii, 226. $69.95 cloth; $24.95 paper) From 1953 until 1988, the Savannah River Plant (SRP) manufactured thirty-six metric tons of plutonium for America’s nuclear arsenal. It also produced tritium for hydrogen bombs. The SRP consisted of five reactors and related facilities for refinement and waste disposal. Thousands of people worked there. The site remains under the control of the federal government but has since been diverted to other uses. It spreads over 310 square miles bordering on Georgia and covering parts of three South Carolina counties. As Kari Frederickson makes clear through her admirably researched and gracefully written book, the SRP encompasses a similarly broad swath of historiographical themes. Other sites like Hanford and Los Alamos have received attention in studies about national defense. Although scholars of the South acknowledge the importance of defense spending and have examined military installations, they have overlooked places such as the SRP and Oak Ridge. Frederickson positions her study within the framework of this literature. In addition, she demonstrates how the SRP shaped the labor movement, the growth of the middle class, the evolution of corporate culture, the increased authority of scientific experts, the rise of the consumer economy, the decline of the Democratic Party in the South, and the end of Jim Crow segregation. Frederickson organizes her book chronologically with each chapter addressing a larger theme. She starts with the 1949 detonation of a fission bomb by the Soviets, which spurred the Truman administration to pursue thermonuclear technology and led to a November 1950 announcement that the DuPont Corporation would build the SRP. She also discusses how the Korean War lent urgency to the effort and how politicians such as James Byrnes, Strom Thurmond, and Mendel Rivers worked to locate the plant in South Carolina. She provides an overview of the area the SRP would affect while [End Page 541] making the case that Aiken County could serve as a lens for examining the entire South. Cotton cultivation dominated the economy. The town of Hamburg was an important railroad terminus during the nineteenth century. Nearby, the textile factory at Graniteville had been a pioneer in mill village paternalism. These also made Aiken County a target during the Civil War and the site of an 1865 battle. Some of the worst racial violence of Reconstruction took place in Hamburg and Ellenton. Despite such incidents, the county served as a tourist destination for affluent “winter colonists.” Other newcomers included Strom Thurmond, who practiced law in Aiken after stepping down as governor. The book’s most poetic chapter is about the removal of eight-thousand people who lived on the site and the destruction of entire towns, including Ellenton. Frederickson writes a compelling analysis of the differing ways in which inhabitants and appraisers conceptualized the value of land. She emphasizes how both viewed their actions in terms of patriotism. She tells how some residents uprooted tombstones to prevent exhumation of their loved ones. She reminds readers that many of the dispossessed were sharecroppers who received no compensation for losing their homes. Construction of the primary SRP facilities occurred between 1951 and 1956, which coincided with campaigns to eliminate racial segregation and give workers the right to organize unions. Although the federal government was ostensibly committed to these twin goals, Frederickson demonstrates that they were overshadowed by Cold War imperatives, DuPont’s corporate culture, local resistance, and the technical requirements of jobs. Unlike Hanford or Oak Ridge, the SRP did not provide employee housing. That experience raised concerns about the governmental control that came with such amenities, so nuclear workers in South Carolina relied upon existing communities. Frederickson explains how this free-market solution overwhelmed the infrastructure and the ability of local officials to manage growth. Subsequently, she describes how the SRP fostered greater social mobility and increased participation by residents of Aiken County in the consumer economy. Part [End Page 542] of this change came through DuPont’s efforts to downplay its role...

36Cl deposition rate reconstruction from bomb pulse until present: A study based on groundwater records

The radioactive isotope 36Cl, with a half-life of 301ka, is a valuable chronometer for estimation of groundwater residence time up to 2 millions of years. Aerial thermonuclear fission bomb tests, performed during the late 1950s, injected a massive amount of this isotope into the atmosphere, which exceeded the natural fallout signal. Since this bomb pulse, atmospheric 36Cl deposition tends to return to natural fallout rate. The monitoring of this attenuation can provide a good opportunity to extend the use of this chronometer to shorter time spans. Venice’s lagoon alimentation zone shows groundwaters with residence times distributed over last fifty years. This permits the estimation of a continuous 36Cl deposition curve, free from latitudinal and seasonal variations of the signal. Three old groundwater samples, with residence times comprised in the range −900 to −8000BP, allow the estimation of a mean natural deposition of 49atm−2s−1 and are in good agreement with 36Cl fallout observed for the last 40,000years by (Plummer et al., 1997). For the bomb pulse period, a fallout of 5300atm−2s−1 was calculated. This was followed by a strong attenuation period, taking place until the 1980s, during which the fallout reached values ranging between 167 and 354atm−2s−1. The attenuation reached then a plateau: it experienced a slower lowering until the actual deposition, with fallout values calculated between 124 and 252atm−2s−1. This persistence of high deposition rate was classically attributed to biological and atmospherical recycling processes or underestimation of the natural atmospheric production of the 36Cl. Additional source of 36Cl production has been envisaged through the activation of chlorine radicals from stratospherical CFCs, leading to a 36Cl production rate comparable with that of Ar spallation from the first approximation. Lastly, the latitudinal factor of the attenuation of the fallout rate is discussed and the impact of the jet streams is proposed as an explanation for the discrepancies in the attenuation rate.

1932, a watershed year in nuclear physics

The consequences, for good and ill, of that annus mirabilis of discovery and invention are still very much with us.

Reclaiming Realism for the Left: Gar Alperovitz and the Decision to Use the Atomic Bomb

Sixty-seven years after the decision to use the atomic bomb in World War II, controversy remains whether the United States was justified in using fission bombs in combat. Gar Alperovitz, the great revisionist historian, in his Atomic Diplomacy and The Decision to Use the Atomic Bomb transformed our knowledge of the geopolitical motives behind the atomic attack against Japan at the end of World War II. These uranium and plutonium-core bombs were political, not primarily military in purpose and motive behind their deployment. His analysis will be compared to realists such as Hans Morgenthau, Kenneth Waltz, Henry Kissinger and George Kennan who for the most part questioned unrestrained violence and offered nuanced views on the wisdom of using such indiscriminate, savage weapons of war. The paper will explore Alperovitz’s classic argument that out of the ashes of Hiroshima and Nagasaki, the A-bomb drove the incipient Cold War conflict. American national-security elites construed the bomb as a political-diplomatic lever to contain Soviet power as much as a military weapon to subdue Japan. The views of various political and military leaders, President Truman, Henry Stimson, James Byrnes, General George C. Marshall, Admiral William Leahy and General Dwight Eisenhower are assessed.

Plutonium and uranium contamination in soils from former nuclear weapon test sites in Australia

The British government performed a number of nuclear weapon tests on Australian territory from 1952 through to 1963 with the cooperation of the Australian government. Nine fission bombs were detonated in South Australia at Emu Junction and Maralinga, and a further three fission weapons were detonated in the Monte Bello Islands off the coast of Western Australia. A number of soil samples were collected by the Australian Radiation Laboratories in 1972 and 1978 during field surveys at these nuclear weapon test sites. They were analysed by gamma spectrometry and, for a select few samples, by alpha spectrometry to measure the remaining activities of fission products, activation products and weapon materials. We have remeasured a number of these Montebello Islands and Emu Junction soil samples using the ANTARES AMS facility, ANSTO. These samples were analysed for plutonium and uranium isotopic ratios and isotopic concentrations. Very low 240Pu/239Pu ratios were measured at both sites (∼0.05 for Alpha Island and ∼0.02 for Emu Field), substantially below global fallout averages. Well correlated but widely varying 236U and plutonium concentrations were measured across both sites, but 233U did not correlate with these other isotopes and instead showed correlation with distance from ground zero, indicating in situ production in the soils.

Oleg Aleksandrovich Lavrentyev

Oleg Aleksandrovich Lavrentyev, regarded as a founding father of Soviet fusion research, died of cardiac arrest on 10 February 2011 in Kharkov, Ukraine.Lavrentyev was born on 7 July 1926 in Pskov, Soviet Union. He became interested in nuclear physics in his youth after reading a book about it, but his quest to learn more was put on hold after the outbreak of World War II. In 1944, with only an eighth-grade education, he crossed the front line and volunteered in the Soviet army as an artilleryman. After the war he continued service in the army as a signalman on Sakhalin Island until July 1950. In the army’s library on the island, Lavrentyev read all the books he could find on math, physics, and chemistry. He learned about the atomic bomb and attempts to create a hydrogen one.Lavrentyev sent a letter to the Kremlin saying, “I know the secret of the hydrogen bomb.” An officer sent by the Kremlin to interrogate Lavrentyev gave him two weeks to put his ideas in writing. In two weeks during July 1950, he secretly wrote the report, in which he confidently declared that a hydrogen bomb could be made with lithium-6 deuteride and initiated by a huge pulse of neutrons from a nuclear fission bomb to create tritium and facilitate deuterium–tritium thermonuclear fusion reactions.In the report, Lavrentyev also advocated developing, for peaceful applications, a nuclear fusion reactor in which spherical electrostatic grids would accelerate and confine plasma. The proposal, made independently before others published their work on the topic, initiated the Soviet program on controlled thermonuclear fusion research. Lavrentyev’s report, which Andrei Sakharov reviewed positively, inspired Sakharov and Igor Tamm to consider using magnetic fields for fusion reactors.Lavrentyev enrolled in Moscow State University in August 1950. During an accelerated program of study, he proposed an “electromagnetic trap” that would confine plasma by electrostatic plugging of magnetic cusps.Several months elapsed before government officials finally contacted Lavrentyev about the report. The nuclear weapons program, overseen by secret police chief Lavrenti Beria, provided him with an apartment and a tutor. But in 1953, before Lavrentyev graduated, Joseph Stalin died, and Beria was executed. People wrongly associated Lavrentyev with Beria, which led to Lavrentyev’s being ostracized and not receiving a promised job at the nuclear weapons development laboratory (now the Kurchatov Institute).In April 1956 Lavrentyev was hired by the Kharkov Physical-Technical Institute (now the Kharkov Institute of Physics and Technology) in Ukraine, where he worked his entire career. In 1966, under the direction of Boris Safronov, he completed his Kandidat dissertation—on electromagnetic traps—at the institute.Lavrentyev built small electromagnetic traps, but he was unable to construct a bigger machine after his supervisor, Anatoly Kalmykov, died and funding was cut. Although he never received adequate financial support, Lavrentyev was still able to pursue his research on a low budget.Lavrentyev developed the theory of plasma confinement and heating in electromagnetic traps; it included the lifetime of ions diffusing in velocity space over the potential barrier and the reduction of the potential barrier by electron space charge in the gaps between the anodes. He analyzed the collisionless heating of ions during electron-beam injection and determined the electron loss rates by diffusion across and along the magnetic field and in velocity space over the electrostatic potential barrier of the cathodes. In his Jupiter 2M experiment, Lavrentyev and his group measured the predicted potential well and demonstrated that electron cross-field diffusional losses were nearly classical.In 2004 Lavrentyev was awarded a doctor of sciences degree by the Kharkov National University for his thesis “Electrostatic and electromagnetic traps of high-temperature plasma.” In his later years, he designed a 4-GW “Elemag” thermonuclear reactor, a powerful neutron source for materials testing. He devised a mechanism to directly convert electron thermal energy into electricity and demonstrated it at low currents. Five students earned their Kandidat degrees under his leadership. He wrote or cowrote more than 100 scientific articles and had 30 inventions. He was named the 2003 Honored Worker in Science and Technology of the Ukraine and was awarded the 2004 K. D. Sinelnikov Prize of the Ukrainian Academy of Sciences for excellence in plasma physics.Lavrentyev will be remembered for his innovative vision, patient persistence, gentle manner, and kindness, and for inspiring the field of nuclear fusion research in the Soviet Union.Oleg Aleksandrovich LavrentyevPPT|High resolution© 2011 American Institute of Physics.

Fission fizzles: Estimating the yield of a predetonated nuclear weapon

An undergraduate-level model is developed for estimating the fraction of the design yield that can be realized if a uranium or a plutonium fission bomb suffers an uncontrolled predetonation due to a spontaneous fission of the fissile material. The model is based on the combination of one published earlier for the predetonation probability and a yield model developed by Mark et al. [“Explosive properties of reactor-grade plutonium,” Sci. Global Secur. 17 (2), 170–185 (2009); a reprint of the same paper published in Sci. Global Secur. 4 (1), 111–128 (1993)].