Fission Bomb Research Articles

Predetonation probability of a fission-bomb core

An undergraduate-level derivation of the probability that a uranium or plutonium fission bomb will suffer an uncontrolled predetonation due to neutrons liberated in spontaneous fissions in the fissile material is developed. Consistent with what was learned by Los Alamos bomb designers during World War II, it is shown why uncontrolled predetonation was not a problem for a U-235 bomb of the Little Boy “gun” design but necessitated development of implosion engineering for the Pu-239 Trinity and Fat Man bombs where the cores were contaminated with highly spontaneously fissile Pu-240.

John von Neumann and Klaus Fuchs: an Unlikely Collaboration

I discuss the origin of the idea of making a fusion (hydrogen) bomb and the physics involved in it, and then turn to the design proposed for one by the unlikely collaborators John von Neumann and Klaus Fuchs in a patent application they filed at Los Alamos in May 1946, which Fuchs passed on to the Russians in March 1948, and which with substantial modifications was tested on the island of Eberiru on the Eniwetok atoll in the South Pacific on May 8, 1951. This test showed that the fusion of deuterium and tritium nuclei could be ignited, but that the ignition would not propagate because the heat produced was rapidly radiated away. Meanwhile, Stanislaw Ulam and C.J. Everett had shown that Edward Teller’s Classical Super could not work, and at the end of December 1950, Ulam had conceived the idea of super compression, using the energy of a fission bomb to compress the fusion fuel to such a high density that it would be opaque to the radiation produced. Once Teller understood this, he invented a greatly improved, new method of compression using radiation, which then became the heart of the Ulam–Teller bomb design, which was tested, also in the South Pacific, on November 1, 1952. The Russians have freely acknowledged that Fuchs gave them the fission bomb, but they have insisted that no one gave them the fusion bomb, which grew out of design involving a fission bomb surrounded by alternating layers of fusion and fission fuels, and which they tested on November 22, 1955. Part of the irony of this story is that neither the American nor the Russian hydrogen-bomb programs made any use of the brilliant design that von Neumann and Fuchs had conceived as early as 1946, which could have changed the entire course of development of both programs.

Secrecy and its fallout at a nuclear weapons plant: A study of Rocky Flats oral histories.

The basis for this study is a large collection of oral histories of persons who were centrally involved in working at, or being impacted by, the Rocky Flats Nuclear Weapons Plant near Denver, Colorado. The oral histories were collected in collaboration between a library-based volunteer oral history project (the Maria Rogers Oral History Program) and a museum that will preserve the history of the plant (Rocky Flats Cold War Museum). Using just these oral histories as the data source, the issue of secrecy and its ramifications are examined. Secrecy as a national security structure and how it affects workers is explored, including how “compartmentalization” and “need to know” played out in the functioning of the manufacturing plant mass-producing the “pit”—the fission bomb that is the detonator of a thermonuclear weapon. The reactions of community members, including regulators, environmental and peace activists, politicians, and concerned citizens, are examined with reference to the issue of the plant's secr...

Ignition of a Deuterium Micro-Detonation with a Gigavolt Super Marx Generator

The Centurion–Halite experiment demonstrated the feasibility of igniting a deuterium–tritium micro-explosion with an energy of not more than a few megajoule, and the Mike test, the feasibility of a pure deuterium explosion with an energy of more than 106 MJ. In both cases the ignition energy was supplied by a fission bomb explosive. While an energy of a few megajoule, to be released in the time required of less than 10−9 s, can be supplied by lasers and intense particle beams, this is not enough to ignite a pure deuterium explosion. Because the deuterium–tritium reaction depends on the availability of lithium, the non-fission ignition of a pure deuterium fusion reaction would be highly desirable. It is shown that this goal can conceivably be reached with a “Super Marx Generator”, where a large number of “ordinary” Marx generators charge (magnetically insulated) fast high voltage capacitors of a second stage Marx generator, called a “Super Marx Generator”, ultimately reaching gigavolt potentials with an energy output in excess of 100 MJ. An intense 107 Ampere-GeV proton beam drawn from a “Super Marx Generator” can ignite a deuterium thermonuclear detonation wave in a compressed deuterium cylinder, where the strong magnetic field of the proton beam entraps the charged fusion reaction products inside the cylinder. In solving the stand-off problem, the stiffness of a GeV proton beam permits to place the deuterium target at a comparatively large distance from the wall of a cavity confining the deuterium micro-explosion.

Edward Teller: The Real Dr. Strangelove (review)

Reviewed by Frank A. Settle Washington & Lee University Lexington, Virginia Edward Teller: The Real Dr. Strangelove. By Peter Goodchild. Cambridge, Mass.: Harvard University Press, 2004. ISBN 0-674-01669-6. Illustrations. Appendixes. Notes and references. Select bibliography. Index. Pp. xxv, 469. $29.95. This excellent biography not only delves into the enigmatic character of this powerful twentieth-century scientist but also provides valuable insights into the role of science and technology in the Cold War. Goodchild, a noted biographer of J. Robert Oppenheimer, uses newly available letters from Teller's friend, physicist Maria Goppert Mayer, as well as personal interviews with Teller and his associates to enrich this work. [End Page 279] The book begins with a description of Teller's family and a childhood in Hungary that was climaxed in 1919 by the brief Communist takeover of the country. This experience embedded a deep distrust of Russia that was to last throughout his life. Other painful experiences in his childhood and adolescence contributed to his personal insecurity. The narrative follows his early professional career from his Ph.D. work with Werner Heisenberg at Munich, a three-year term as an assistant professor at the University of Göttingen, a research fellowship with Neils Bohr in Copenhagen, and finally to the United States where he accepted George Gamow's offer of a position in the physics department of George Washington University. In 1939, learning of the discovery of fission, Teller, along with Leo Szilard and Eugene Wigner, two other emigrant physicists, persuaded Albert Einstein to send the letter to President Roosevelt that became the catalyst for the Manhattan Project. After Pearl Harbor, Teller joined the group of scientists at the University of Chicago who were working on the development of the first nuclear weapon, a fission bomb. Here he began to develop his ideas for a more powerful thermonuclear fusion bomb known as the "Super." While working with the leaders of the nascent Manhattan Project in Chicago, he was invited to Los Alamos by J. Robert Oppenheimer. At Los Alamos, Teller, still preoccupied with the "Super," was disappointed when Oppenheimer, the lab director, appointed Hans Bethe to head the Theoretical Division. This was the beginning of the rift between Teller and Oppenheimer which culminated in Oppenheimer's loss of security clearance in 1954. Teller witnessed the Trinity test in July 1945 and, after the war ended, remained at Los Alamos to continue work on the "Super." This work was driven in no small part by his fear that Russia would become a more dangerous enemy than Germany. Teller continued to promote the "Super" in the political and scientific communities despite the opposition of many members of both. In 1949, bolstered by the Soviets' detonation of a fission weapon, Teller increased his efforts to convince the United States government to develop the "Super." His alliance with members of Congress, Lewis Strauss, an Atomic Energy (AEC) Commissioner, and a few scientific colleagues was opposed by a group of scientists that included Oppenheimer. In early 1950, President Truman directed the AEC to develop the hydrogen bomb as a defensive measure against any possible aggressor. However, the work on the "Super" at Los Alamos was impeded by a committee chaired by Oppenheimer which recommended that the laboratory should concentrate on fission weapons. Teller again prevailed and a fission bomb was used to initiate the fusion of a small amount of a deuterium-tritium mixture in the George test in the Pacific in 1951. The first full-scale thermonuclear explosion, the Mike test, occurred in November 1952 with an absent Teller watching its effects on a seismograph from a California laboratory. The success of the test and the animosity between Teller and the scientists at Los Alamos led him to ally with Ernest Lawrence to form a second nuclear weapons laboratory on the site of an old naval air station at Livermore, California. A keen rivalry developed between the two laboratories that lasted through the remainder of the...

Bearing Your Right Arm

Bearing Your Right Arm Dan Olds (bio) Recently, our government allowed an assault rifle ban to fade away. I see this as a first step in the right direction. Nothing complements the warm fuzzy feeling I get hearing the little birds in the trees chirping quite like the pleasant "klackity-klak" of an AK-47. Some ask why anyone would need an assault rifle. Well, I ask if you know of a better way to deal with a squirrel than with an Uzi. Yeah, I say let us hope this is only the first step on a path toward a bright, shell-filled future. A future in which many tools, currently listed as military ordinance, could be used to make things a little easier around the house and yard. Tree need to come down? Plastic explosives would save you so much time. Someone block you into your driveway? A small rocket-propelled grenade can easily relocate this sir or madam's misplaced vehicle. Don't want rabbits in your garden? Plant a mine field. If a rabbit does wander in, hey, free fertilizer. And you can't tell me there's a better way to keep the dog off the couch than a few well-timed warning blasts from a flame thrower. I find that exponentially more effective than a rolled-up newspaper. Some of you are pulling away from me at this point, but please, let me explain. Our country was founded with guns as they helped us defeat the British. Our founding fathers, seeing them as such, made them protected in our constitution. See, guns are there to help us as tools, but also to put one more check and balance in our governing body. This leads me to my next point. The plan was, if the government ever became tyrannical, unrepresentative of the people, it could and should be overthrown. Do you really believe, however, that you could successfully rebel against the government with your current stash of post-apocalyptic goodies? No, they have jets and armies to protect them. This means they won't respect your opinion if you have much less than a tank sitting in your garage. So I say it's time to bring control back to the little guy. It's time to stand up and be heard by the powers that be. It's time for each and every American to install his or her very own tactical ICMB missile silo with a personal fission bomb resting peacefully inside. [End Page 35] Can you imagine what a beautiful world this would be? Pull up into your driveway, your neighbor comes over (no need to pull out the sawed-off shotgun, mind you; this is the neighbor you like). "Morning Ted, I see you have the missile out in 'Ready' mode today." "Yeah, well, you know George, it needed a quick wipe down and I find it keeps those pesky kids who play hockey in the street away from the flower bed." "Yes, your daylilies are coming in great." "Thanks, it's all that chipmunk fertilizer you gave me; the stuff works something wonderful." So I say lift those bans, twitch those trigger fingers, and bring on that military ordinance. I'm seeing a bright, shiny, noisy, tactical future America, and it looks great. Now get out of my yard. Dan Olds Dan Olds began his academic career trying to solve the mysteries of existence with physics and philosophy. He failed. Moving on to search for the answers in art, he discovered he wrote bad poetry, took ugly photographs, and painted a horrible picture. Distraught with his lack of talent, Dan turned to satire. Finding a natural outlet for his bitterness towards stupidity, he vowed to fight social acceptance of moronic ideals to the bitter end. To this day he is still fighting and by the looks of things, losing. Copyright © 2005 Michigan State University

Heisenberg’s Message to Bohr: Who Knows?

Heisenberg’s Message to Bohr: Who Knows?

Classification of hot particles from the Chernobyl accident and nuclear weapons detonations by non-destructive methods

Both after the Chernobyl accident and nuclear weapon detonations, agglomerates of radioactive material, so-called hot particles, were released or formed which show a behaviour in the environment quite different from the activity released in gaseous or aerosol form. The differences in their characteristic properties, in the radionuclide composition and the uranium and actinide contents are described in detail for these particles. While nuclear bomb hot particles (both from fission and fusion bombs) incorporate well detectable trace amounts of 60Co and 152Eu, these radionuclides are absent in Chernobyl hot particles. In contrast, Chernobyl hot particles contain 125Sb and 144Ce which are absent in atomic bomb HPs. Obvious differences are also observable between fusion and fission bombs’ hot particles (significant differences in 152Eu/ 155Eu, 154Eu/ 155Eu and 238Pu/ 239Pu ratios) which facilitate the identification of HPs of unknown provensence. The ratio of 239Pu/ 240Pu in Chernobyl hot particles could be determined by a non-destructive method at 1 : 1.5. A non-destructive method to determine the content of non-radioactive elements by K α -emission measurements was developed by which inactive Zr, Nb, Fe and Ni could be verified in the particles.

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 Noble 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 235U 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/d 235U 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/d 235U 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 beta tank.

Thermonuclear Milestones: (2) Beginnings of the Soviet H‐Bomb Program

In late 1945 Soviet physicist Yakov Il'ich Frenkel suggested that fission bombs might be used to fuse light nuclei and thus release even greater energies. In a memo addressed to Igor Vasilievich Kurchatov dated 22 September 1945, he pointed out that “it would be in our best interest to utilize the high, billion‐degree temperatures developed in the explosion of an atomic bomb in application to synthetic reactions (for example, to produce helium from hydrogen), which are the energy source of stars and which could even further increase the energy released in the explosion of the principal substance (uranium, bismuth, lead),” Despite the error in estimating the temperatures in an atomic explosion and the fallacy of suggesting that bismuth and lead nuclei are fissionable, the thought expressed by Frenkel is significant as the first documented Soviet communication on the topic.

Highly enriched uranium production for South African nuclear weapons

We estimate that South Africa produced 735 ± 53 kilograms of the equivalent of 90 per‐cent‐highly enriched uranium (HEU). This amount, were it enriched to 80 to 90 percent, could be used to construct 12 Hiroshima‐type fission bombs. The South African government maintains it constructed only six such devices, and never intended to construct more than seven. The excess HEU was apparently less enriched than that desired by South Africa for its weapons, but probably still weapons‐usable. Implosion‐type devices were apparently being researched at the time the nuclear weapons program was dismantled in 1989. Had this effort continued, eventually South Africa would have been able to construct four times as many weapons from the same amount of fissile material. Because of a 15.6 percent uncertainty in the tails assay, the two standard deviation uncertainty in the amount of U‐235 in the HEU produced is 256 kilograms. It is in the interest of all parties to reduce this uncertainty.

Radiological weapons and radioactive waste in the United States: insiders' and outsiders' views, 1941-55.

The Manhattan Project to develop an atomic bomb, the atomic bombs on Hiroshima and Nagasaki, and the post-war nuclear arms race with fission and fusion bombs have been the subject of many discussions and historical studies. In fact, these subjects, and the way in which they were generally dealt with, have led to retrospective distortion with respect to the spectrum of ‘atomic’ weapons discussed and explored during the wartime Manhattan Project and immediately after the Second World War. Specifically, it has made observers of the cold war's early nuclear arms race overlook the fact that the military use of radioactive reactor fission products in so-called radiological warfare weapons, was a very real possibility at the time, both for the US Atomic Energy Commission (AEC) and the military, as well as for relative outsiders and the general public. Thus, for many observers it came as something of a surprise when the United States in 1976 introduced radiological weapons as an issue of UN arms control negotiations between the United States and the Soviet Union.

Accelerator-Measured 14C Activity in Tree Rings From the Vicinity of the First Atomic Bomb Test

Detonation of the first fission bomb at White Sands, New Mexico, on July 16, 1945, produced a tremendous neutron flux capable of creating tritium and radiocarbon byproducts. We sampled a 115-year-old pinyon (Pinus edulis) 10km east of the Trinity test site to determine 14C evidence of this event. The most likely mechanism for this enrichment in the 1945 tree ring would be fixation of 14CO2 produced at the blast site and carried with the fallout cloud over the pinyon site. Analysis of cellulose of the 1944 and 1945 rings shows δ13C values of −19.9 and −19.5, respectively, and 14C activity (fraction of modern uncorrected for δ13C) as 0.991 ± .005 and 0.991 ± .006, respectively. It is likely that the duration and/or concentration of the 14CO2 exposure was not sufficient to increase 14C activity expected for that year.

Committe Reviews DOE Inertial‐Confinement Fusion Program

Inertial‐confinement fusion clearly works. It's demonstrated every time a hydrogen bomb is detonated. But is it possible to ignite a small deuteriumtritium pellet under controlled conditions in the laboratory—driving the requisite implosion with anything less drastic than a fission bomb?

Current Toll of the Final Epidemic: Death and Illness from the Weapons Race

If some of the nuclear weapons in the world's arsenals were actually detonated, what would happen to people, the environment, and our social fabric? The answers to this question have been made more widely known in recent years as Physicians for Social Responsibility and other antinuclear war groups have made a concentrated and relatively successful effort to educate health workers and the public on the catastrophic destruction that nuclear war would bring. The types of destruction from the use of the weapons are predictable from the known short-term and long-term consequences of the kilotonrange fusion (nuclear) bombs dropped on Hiroshima and Nagasaki, from the tests of megaton-range fission (' 'thermonuclear' ') bombs, and from increasingly sophisticated computer simulations. Immediate effects are due to the blast, heat, and direct radiation from the explosion. It has been estimated that a 1 -megaton bomb detonated in the air above New York City could cause 1 . 1 million prompt deaths and 3.4 million serious injuries. A nuclear exchange between the United States and the USSR, it has been estimated, could produce 140 million prompt deaths in the United States and 113 million in the USSR.

Economy of Fusion

By DIETRICK E. THOMSEN A s 1984 begins, so do the inevitable reminiscences of George Orwell. But while Orwell was composing his pessimistic view of his future (our present), others were advancing optimistic ones either to boost the morale of those involved in a war or to amaze those attending a world's fair. The optimistic genre tended to share certain assumptions: Clothing would be light and abbreviated. Giant domes built over whole cities would control microclimates. Public transport would be readily available and well patronized. And power for all this would be generated by smokeless means. Of these predictions the only one that has come true is the one about abbreviated clothing. In any North American city, numbers of people can be seen running around the streets or lying in parks in their underwear (or what seems to be less), an activity for which they would have been arrested during the 1940s. Nobody has yet domed a city. Public transport in the United States is in terrible shape. And most of our electricity still comes from fossil fuels. The smokeless power was supposed to come from nuclear fission or nuclear fusion. Fission reactors were available in the 1940s and were expected to sweep the power industry. They have not done so. Ironically the economics seem more against them than for them. Fusion reactors don't yet exist, though by 1940s predictions they should exist by now. Scientific difficulties and the example of nonproliferation of fission power reactors have led to questioning of the fusion program. People wonder particularly whether fusion economics would be similarly disappointing. Even most researchers in the field tend to talk diffidently about its prospects. One who is not diffident is John Nuckolls, who was recently promoted to be director of physics at the Lawrence Livermore National Laboratory in Livermore, Calif. Nuckolls has called for a crash program, like the Manhattan District Project that got us both fission bombs and fission reactors, to get us fusion reactors. Having made that call, he decided to study what the economics of fusion power are likely to be. He discussed that study in a recent interview with SCIENcE NEws. Nuckolls is concerned that his colleagues in the fusion effort, who are busily working toward a scientific demonstration of the feasibility of fusion, are not paying enough attention to what happens afterward. If! were in [Presidential Science Advisor George A.] Keyworth s position, he says, I would get the fusion community together and say, people have to worry that you're going to get into the same boat as NASA was when it got a man on the moon. It will be a great triumph when the tokamak works and you get breakeven or whatever it is... But what comes after that? If you look at what happened to the NASA budget for the next decade, it didn't go up, it sort of went down, and people haven't been back to the moon since. I'm afraid that fusion is racing toward another anticlimax because they're not putting enough effort into what happens after [breakeven]. The is going to need increases in available power, he contends. Even assuming that the population levels off after another doubling and that the average person makes only a modest increase in power demand, he quotes estimates of 10,000 fission reactors. Multiplying by an estimated unit cost of a billion dollars means $10 trillion are at stake. All those world of tomorrow brochures assumed that the smokeless power was going to be cheap. When fusion was first getting started, why it was cheap, clean and inexhaustible. Fusion and fission were both the same, except that fission wasn't clean.... They weren't even going to charge you for it. Now we're in a where economics really matters. It is more of a zero-sum game. Its not sufficient for fusion to be the same price as fission or coal or whatever the competition is. It has got to be substantially cheaper, or the utilities are not going to want to go to the trouble to install a new energy system....I think the nature of technology is that nobody can make a perfect product. You sort of do it by iteration, by trial and error, and its pretty expensive to do that on half billion and billion and two billion dollar facilities, particularly when you've got environmental groups nipping at your heels. Coal is not going to escape. All these developing countries are not going to rush to buy an expensive fission or fusion plant if they can burn their own coal, which they mine with cheap labor. The is doomed to fall into the CO2 trap [the i-1

The Possibility of Micro-fission Chain-reactions and their Application to the Controlled Release of Thermonuclear Energy

It had been shown 1, 2 recently that it may be possible to reach densities up to 103 g/cm3 by imploding a solid hydrogen pellet with the aid of a symmetric arrangement of multiple laser beams irradiating the pellet simultaneously from all sides. The purpose of this proposed scheme was to reduce the energy input requirements for the controlled release of thermonuclear energy delivered by laser ignited T - D micro-explosion systems. It is shown in this paper that by applying the foregoing concept of high density compression to a pellet consisting of fissionable material such as U235, Pu239, or U223, the critical mass for the initiation of a fission chain reaction in these materials can be reduced by many orders of magnitude raising the possibility of micro-fission-explosions with laser energy inputs for compression within the expected reach of laser technology. Alternatively, the pellet compression may be also achieved by the employment of intense relativistic electron beams. In addition, by surrounding the fis­sionable pellet with a layer of dense T - D material to be compressed together with the pellet, the minimum pellet size can be furthermore reduced by neutron reflection from the high neutron albedo T - D shell. For fissionable pellets without a reflector the critical mass can be as small as ∼ 0.3 g requiring a laser energy input for compression of several megajoule. For a pellet surrounded by a T - D reflector the critical mass can be reducel down to ∼10-3g with a laser energy input for compression of several 105 joule. In addition to the neutron albedo effect of the T - D shell there is a bootstrap mechanism where­by the T - D mantle achieves thermonuclear temperatures resulting in the emission of thermo­nuclear reaction neutrons into the fissionable pellet causing more fission reactions and thereby raising the temperature of the pellet. This then in turn will lead to an additional heating of the T - D blanket resulting in an increased flux of thermonuclear neutrons raising the fission rate even further. Because of the greatly increased material density, a fission chain reaction initiated in it will grow in proportion much faster than in uncompressed fissionable material as it is being used in conventional fission bombs. The system described may have important usefulness as a small fission power plant especially for space propulsion applications but also for a more effective burn in a thermonuclear micro-bomb reactor as a fission supported fusion reaction.

Food pollution by radioactive fallout caused by fission and fusion bomb tests in Red China

Food pollution by radioactive fallout caused by fission and fusion bomb tests in Red China

Atmospheric bomb radiocarbon as a tracer in human beings.

The level of radiocarbon in atmospheric carbon dioxide has risen to almost double the natural or reference level of 1890 (about 14 dpm per gram of carbon) as a result of the testing of fission and fusion bombs. It has reached a concentration that can be measured in living tissues by low-level carbon-14 counting equipment.

Radioactive hazard resulting from the explosions of a ‘clean’ hydrogen bomb and of a conventional fission bomb

An estimate is made of the danger to the world population arising from the creation of long-lived radioactive isotopes in nuclear explosions and from their dissemination over the globe. An ordinary fission bomb and a clean hydrogen bomb, taken to be a deuterium-tritium reaction, are considered. With a hydrogen bomb the principal agents are 14C and 8H, and with an ordinary bomb 90Sr, 137Cs and 1°C. The doses delivered to the gonads and bones are calculated, and this leads to figures for the number of people born subsequently with hereditary defects and the number of cases of leukaemia (cancer of the blood). In this calculation the distribution of radioisotopes in animate and in inanimate matter is taken into account. The special aspects of a ground-level hydrogen explosion are considered. The total amount of energy liberated in radioactive decay by products of the explosion is three times greater in the case of a deuterium-tritium bomb than for an ordinary bomb. However, taking an estimate over the whole period of decay of the reaction products, it is found that ten-megaton bombs of the two types give rise to roughly the same dose of radiation to the tissues, and claim approximately the same number of victims. In round figures we expect: Deuterium-tritium bombFission bomb Dose to the tissues50,000 x 10−6 r40,000 x 10−6 r, Dose to the bones50,000 x 10−6 r88,000 x 10−6 r Number of mutations (in a population of 2·5 x 109)50,00040,000 Number of cases of leukaemia (in a population of 2·5 x 108)15,00026,000 Thus on the score of radiation injury to the world population, a clean hydrogen bomb operating by the reaction of. deuterium and tritium cannot be considered less dangerous than an ordinary atomic bomb.