Many of our readers associate the hydrogen bomb with an atomic one, only much more powerful. In fact, this is a fundamentally new weapon, which required disproportionately large intellectual efforts for its creation and works on fundamentally different physical principles.
"Puff"
Modern bomb
The only thing that the atomic and hydrogen bombs have in common is that both release colossal energy hidden in the atomic nucleus. This can be done in two ways: to divide heavy nuclei, for example, uranium or plutonium, into lighter ones (fission reaction) or to force the lightest isotopes of hydrogen to merge (fusion reaction). As a result of both reactions, the mass of the resulting material is always less than the mass of the original atoms. But mass cannot disappear without a trace - it turns into energy according to Einstein’s famous formula E=mc2.
A-bomb
To create an atomic bomb, a necessary and sufficient condition is to obtain fissile material in sufficient quantity. The work is quite labor-intensive, but low-intellectual, lying closer to the mining industry than to high science. The main resources for the creation of such weapons are spent on the construction of giant uranium mines and enrichment plants. Evidence of the simplicity of the device is the fact that less than a month passed between the production of the plutonium needed for the first bomb and the first Soviet nuclear explosion.
Let us briefly recall the operating principle of such a bomb, known from school physics courses. It is based on the property of uranium and some transuranium elements, for example, plutonium, to release more than one neutron during decay. These elements can decay either spontaneously or under the influence of other neutrons.
The released neutron can leave the radioactive material, or it can collide with another atom, causing another fission reaction. When a certain concentration of a substance (critical mass) is exceeded, the number of newborn neutrons, causing further fission of the atomic nucleus, begins to exceed the number of decaying nuclei. The number of decaying atoms begins to grow like an avalanche, giving birth to new neutrons, that is, a chain reaction occurs. For uranium-235, the critical mass is about 50 kg, for plutonium-239 - 5.6 kg. That is, a ball of plutonium weighing slightly less than 5.6 kg is just a warm piece of metal, and a mass of slightly more lasts only a few nanoseconds.
The actual operation of the bomb is simple: we take two hemispheres of uranium or plutonium, each slightly less than the critical mass, place them at a distance of 45 cm, cover them with explosives and detonate. The uranium or plutonium is sintered into a piece of supercritical mass, and a nuclear reaction begins. All. There is another way to start a nuclear reaction - to compress a piece of plutonium with a powerful explosion: the distance between the atoms will decrease, and the reaction will begin at a lower critical mass. All modern atomic detonators operate on this principle.
The problems with the atomic bomb begin from the moment we want to increase the power of the explosion. Simply increasing the fissile material is not enough - as soon as its mass reaches a critical mass, it detonates. Various ingenious schemes were invented, for example, to make a bomb not from two parts, but from many, which made the bomb begin to resemble a gutted orange, and then assemble it into one piece with one explosion, but still, with a power of over 100 kilotons, the problems became insurmountable.
H-bomb
But fuel for thermonuclear fusion does not have a critical mass. Here the Sun, filled with thermonuclear fuel, hangs overhead, a thermonuclear reaction has been going on inside it for billions of years, and nothing explodes. In addition, during the synthesis reaction of, for example, deuterium and tritium (heavy and superheavy isotope of hydrogen), energy is released 4.2 times more than during the combustion of the same mass of uranium-235.
Making the atomic bomb was an experimental rather than a theoretical process. The creation of a hydrogen bomb required the emergence of completely new physical disciplines: the physics of high-temperature plasma and ultra-high pressures. Before starting to construct a bomb, it was necessary to thoroughly understand the nature of the phenomena that occur only in the core of stars. No experiments could help here - the researchers’ tools were only theoretical physics and higher mathematics. It is no coincidence that a gigantic role in the development of thermonuclear weapons belongs to mathematicians: Ulam, Tikhonov, Samarsky, etc.
Classic super
By the end of 1945, Edward Teller proposed the first hydrogen bomb design, called the "classic super". To create the monstrous pressure and temperature necessary to start the fusion reaction, it was supposed to use a conventional atomic bomb. The “classic super” itself was a long cylinder filled with deuterium. An intermediate “ignition” chamber with a deuterium-tritium mixture was also provided - the synthesis reaction of deuterium and tritium begins at a lower pressure. By analogy with a fire, deuterium was supposed to play the role of firewood, a mixture of deuterium and tritium - a glass of gasoline, and an atomic bomb - a match. This scheme was called a “pipe” - a kind of cigar with an atomic lighter at one end. Soviet physicists began to develop the hydrogen bomb using the same scheme.
However, mathematician Stanislav Ulam, using an ordinary slide rule, proved to Teller that the occurrence of a fusion reaction of pure deuterium in a “super” is hardly possible, and the mixture would require such an amount of tritium that to produce it it would be necessary to practically freeze the production of weapons-grade plutonium in the United States.
Puff with sugar
In mid-1946, Teller proposed another hydrogen bomb design - the “alarm clock”. It consisted of alternating spherical layers of uranium, deuterium and tritium. During the nuclear explosion of the central charge of plutonium, the necessary pressure and temperature were created for the start of a thermonuclear reaction in other layers of the bomb. However, the “alarm clock” required a high-power atomic initiator, and the United States (as well as the USSR) had problems producing weapons-grade uranium and plutonium.
In the fall of 1948, Andrei Sakharov came to a similar scheme. In the Soviet Union, the design was called “sloyka”. For the USSR, which did not have time to produce weapons-grade uranium-235 and plutonium-239 in sufficient quantities, Sakharov’s puff paste was a panacea. And that's why.
In a conventional atomic bomb, natural uranium-238 is not only useless (the neutron energy during decay is not enough to initiate fission), but also harmful because it eagerly absorbs secondary neutrons, slowing down the chain reaction. Therefore, 90% of weapons-grade uranium consists of the isotope uranium-235. However, neutrons resulting from thermonuclear fusion are 10 times more energetic than fission neutrons, and natural uranium-238 irradiated with such neutrons begins to fission excellently. The new bomb made it possible to use uranium-238, which had previously been considered a waste product, as an explosive.
The highlight of Sakharov’s “puff pastry” was also the use of a white light crystalline substance, lithium deuteride 6LiD, instead of acutely deficient tritium.
As mentioned above, a mixture of deuterium and tritium ignites much more easily than pure deuterium. However, this is where the advantages of tritium end, and only disadvantages remain: in its normal state, tritium is a gas, which causes difficulties with storage; tritium is radioactive and decays into stable helium-3, which actively consumes much-needed fast neutrons, limiting the bomb's shelf life to a few months.
Non-radioactive lithium deutride, when irradiated with slow fission neutrons - the consequences of an atomic fuse explosion - turns into tritium. Thus, the radiation from the primary atomic explosion instantly produces a sufficient amount of tritium for a further thermonuclear reaction, and deuterium is initially present in lithium deutride.
It was just such a bomb, RDS-6s, that was successfully tested on August 12, 1953 at the tower of the Semipalatinsk test site. The power of the explosion was 400 kilotons, and there is still debate over whether it was a real thermonuclear explosion or a super-powerful atomic one. After all, the thermonuclear fusion reaction in Sakharov’s puff paste accounted for no more than 20% of the total charge power. The main contribution to the explosion was made by the decay reaction of uranium-238 irradiated with fast neutrons, thanks to which the RDS-6s ushered in the era of the so-called “dirty” bombs.
The fact is that the main radioactive contamination comes from decay products (in particular, strontium-90 and cesium-137). Essentially, Sakharov’s “puff pastry” was a giant atomic bomb, only slightly enhanced by a thermonuclear reaction. It is no coincidence that just one “puff pastry” explosion produced 82% of strontium-90 and 75% of cesium-137, which entered the atmosphere over the entire history of the Semipalatinsk test site.
American bombs
However, it was the Americans who were the first to detonate the hydrogen bomb. On November 1, 1952, the Mike thermonuclear device, with a yield of 10 megatons, was successfully tested at Elugelab Atoll in the Pacific Ocean. It would be hard to call a 74-ton American device a bomb. “Mike” was a bulky device the size of a two-story house, filled with liquid deuterium at a temperature close to absolute zero (Sakharov’s “puff pastry” was a completely transportable product). However, the highlight of “Mike” was not its size, but the ingenious principle of compressing thermonuclear explosives.
Let us recall that the main idea of a hydrogen bomb is to create conditions for fusion (ultra-high pressure and temperature) through a nuclear explosion. In the “puff” scheme, the nuclear charge is located in the center, and therefore it does not so much compress the deuterium as scatter it outwards - increasing the amount of thermonuclear explosive does not lead to an increase in power - it simply does not have time to detonate. This is precisely what limits the maximum power of this scheme - the most powerful “puff” in the world, the Orange Herald, blown up by the British on May 31, 1957, yielded only 720 kilotons.
It would be ideal if we could make the atomic fuse explode inside, compressing the thermonuclear explosive. But how to do that? Edward Teller put forward a brilliant idea: to compress thermonuclear fuel not with mechanical energy and neutron flux, but with the radiation of the primary atomic fuse.
In Teller's new design, the initiating atomic unit was separated from the thermonuclear unit. When the atomic charge was triggered, X-ray radiation preceded the shock wave and spread along the walls of the cylindrical body, evaporating and turning the polyethylene inner lining of the bomb body into plasma. The plasma, in turn, re-emited softer X-rays, which were absorbed by the outer layers of the inner cylinder of uranium-238 - the “pusher”. The layers began to evaporate explosively (this phenomenon is called ablation). Hot uranium plasma can be compared to the jets of a super-powerful rocket engine, the thrust of which is directed into the cylinder with deuterium. The uranium cylinder collapsed, the pressure and temperature of the deuterium reached a critical level. The same pressure compressed the central plutonium tube to a critical mass, and it detonated. The explosion of the plutonium fuse pressed on the deuterium from the inside, further compressing and heating the thermonuclear explosive, which detonated. An intense stream of neutrons splits the uranium-238 nuclei in the “pusher”, causing a secondary decay reaction. All this managed to happen before the moment when the blast wave from the primary nuclear explosion reached the thermonuclear unit. The calculation of all these events, occurring in billionths of a second, required the brainpower of the strongest mathematicians on the planet. The creators of “Mike” experienced not horror from the 10-megaton explosion, but indescribable delight - they managed not only to understand the processes that in the real world occur only in the cores of stars, but also to experimentally test their theories by setting up their own small star on Earth.
Bravo
Having surpassed the Russians in the beauty of the design, the Americans were unable to make their device compact: they used liquid supercooled deuterium instead of Sakharov’s powdered lithium deuteride. In Los Alamos they reacted to Sakharov’s “puff pastry” with a bit of envy: “instead of a huge cow with a bucket of raw milk, the Russians use a bag of powdered milk.” However, both sides failed to hide secrets from each other. On March 1, 1954, near the Bikini Atoll, the Americans tested a 15-megaton bomb “Bravo” using lithium deuteride, and on November 22, 1955, the first Soviet two-stage thermonuclear bomb RDS-37 with a power of 1.7 megatons exploded over the Semipalatinsk test site, demolishing almost half of the test site. Since then, the design of the thermonuclear bomb has undergone minor changes (for example, a uranium shield appeared between the initiating bomb and the main charge) and has become canonical. And there are no more large-scale mysteries of nature left in the world that could be solved with such a spectacular experiment. Perhaps the birth of a supernova.
The explosion occurred in 1961. Within a radius of several hundred kilometers from the test site, a hasty evacuation of people took place, as scientists calculated that all houses without exception would be destroyed. But no one expected such an effect. The blast wave circled the planet three times. The landfill remained a “blank slate”; all the hills on it disappeared. Buildings turned to sand in a second. A terrible explosion was heard within a radius of 800 kilometers.
If you think that the atomic warhead is the most terrible weapon of mankind, then you do not yet know about the hydrogen bomb. We decided to correct this oversight and talk about what it is. We have already talked about and.
A little about the terminology and principles of work in pictures
Understanding what a nuclear warhead looks like and why, it is necessary to consider the principle of its operation, based on the fission reaction. First, an atomic bomb detonates. The shell contains isotopes of uranium and plutonium. They disintegrate into particles, capturing neutrons. Next, one atom is destroyed and the fission of the rest is initiated. This is done using a chain process. At the end, the nuclear reaction itself begins. The bomb's parts become one whole. The charge begins to exceed critical mass. With the help of such a structure, energy is released and an explosion occurs.
By the way, a nuclear bomb is also called an atomic bomb. And hydrogen is called thermonuclear. Therefore, the question of how an atomic bomb differs from a nuclear bomb is inherently incorrect. It is the same. The difference between a nuclear bomb and a thermonuclear bomb is not only in the name.
The thermonuclear reaction is based not on the fission reaction, but on the compression of heavy nuclei. A nuclear warhead is the detonator or fuse for a hydrogen bomb. In other words, imagine a huge barrel of water. An atomic rocket is immersed in it. Water is a heavy liquid. Here the proton with sound is replaced in the hydrogen nucleus by two elements - deuterium and tritium:
- Deuterium is one proton and a neutron. Their mass is twice that of hydrogen;
- Tritium consists of one proton and two neutrons. They are three times heavier than hydrogen.
Thermonuclear bomb tests
, the end of World War II, a race began between America and the USSR and the world community realized that a nuclear or hydrogen bomb was more powerful. The destructive power of atomic weapons began to attract each side. The United States was the first to make and test a nuclear bomb. But it soon became clear that it could not be large. Therefore, it was decided to try to make a thermonuclear warhead. Here again America succeeded. The Soviets decided not to lose the race and tested a compact but powerful missile that could be transported even on a regular Tu-16 aircraft. Then everyone understood the difference between a nuclear bomb and a hydrogen bomb.
For example, the first American thermonuclear warhead was as tall as a three-story building. It could not be delivered by small transport. But then, according to developments by the USSR, the dimensions were reduced. If we analyze, we can conclude that these terrible destructions were not that great. In TNT equivalent, the impact force was only a few tens of kilotons. Therefore, buildings were destroyed in only two cities, and the sound of a nuclear bomb was heard in the rest of the country. If it were a hydrogen rocket, all of Japan would be completely destroyed with just one warhead.
A nuclear bomb with too much charge may explode inadvertently. A chain reaction will begin and an explosion will occur. Considering the differences between nuclear atomic and hydrogen bombs, it is worth noting this point. After all, a thermonuclear warhead can be made of any power without fear of spontaneous detonation.
This interested Khrushchev, who ordered the creation of the most powerful hydrogen warhead in the world and thus get closer to winning the race. It seemed to him that 100 megatons was optimal. Soviet scientists pushed themselves hard and managed to invest 50 megatons. Tests began on the island of Novaya Zemlya, where there was a military training ground. To this day, the Tsar Bomba is called the largest bomb exploded on the planet.
The explosion occurred in 1961. Within a radius of several hundred kilometers from the test site, a hasty evacuation of people took place, as scientists calculated that all houses without exception would be destroyed. But no one expected such an effect. The blast wave circled the planet three times. The landfill remained a “blank slate”; all the hills on it disappeared. Buildings turned to sand in a second. A terrible explosion was heard within a radius of 800 kilometers. The fireball from the use of such a warhead as the universal destroyer runic nuclear bomb in Japan was visible only in cities. But from the hydrogen rocket it rose 5 kilometers in diameter. The mushroom of dust, radiation and soot grew 67 kilometers. According to scientists, its cap was a hundred kilometers in diameter. Just imagine what would have happened if the explosion had occurred within the city limits.
Modern dangers of using the hydrogen bomb
We have already examined the difference between an atomic bomb and a thermonuclear one. Now imagine what the consequences of the explosion would have been if the nuclear bomb dropped on Hiroshima and Nagasaki had been a hydrogen bomb with a thematic equivalent. There would be no trace left of Japan.
Based on the test results, scientists concluded the consequences of a thermonuclear bomb. Some people think that a hydrogen warhead is cleaner, meaning it is not actually radioactive. This is due to the fact that people hear the name “water” and underestimate its deplorable impact on the environment.
As we have already figured out, a hydrogen warhead is based on a huge amount of radioactive substances. It is possible to make a rocket without a uranium charge, but so far this has not been used in practice. The process itself will be very complex and costly. Therefore, the fusion reaction is diluted with uranium and a huge explosion power is obtained. The radioactive fallout that inexorably falls on the drop target is increased by 1000%. They will harm the health of even those who are tens of thousands of kilometers from the epicenter. When detonated, a huge fireball is created. Everything that comes within its radius of action is destroyed. The scorched earth may be uninhabitable for decades. Absolutely nothing will grow over a vast area. And knowing the strength of the charge, using a certain formula, you can calculate the theoretically contaminated area.
Also worth mentioning about such an effect as nuclear winter. This concept is even more terrible than destroyed cities and hundreds of thousands of human lives. Not only the dump site will be destroyed, but virtually the entire world. At first, only one territory will lose its habitable status. But a radioactive substance will be released into the atmosphere, which will reduce the brightness of the sun. This will all mix with dust, smoke, soot and create a veil. It will spread throughout the planet. The crops in the fields will be destroyed for several decades to come. This effect will provoke famine on Earth. The population will immediately decrease several times. And nuclear winter looks more than real. Indeed, in the history of mankind, and more specifically, in 1816, a similar case was known after a powerful volcanic eruption. There was a year without summer on the planet at that time.
Skeptics who do not believe in such a coincidence of circumstances can be convinced by the calculations of scientists:
- When the Earth cools by a degree, no one will notice it. But this will affect the amount of precipitation.
- In autumn there will be a cooling of 4 degrees. Due to the lack of rain, crop failures are possible. Hurricanes will begin even in places where they have never existed.
- When temperatures drop a few more degrees, the planet will experience its first year without summer.
- This will be followed by the Little Ice Age. The temperature drops by 40 degrees. Even in a short time it will be destructive for the planet. On Earth there will be crop failures and the extinction of people living in the northern zones.
- Afterwards the ice age will come. Reflection of the sun's rays will occur without reaching the surface of the earth. Due to this, the air temperature will reach a critical level. Crops and trees will stop growing on the planet, and water will freeze. This will lead to the extinction of most of the population.
- Those who survive will not survive the final period - an irreversible cold snap. This option is completely sad. It will be the real end of humanity. The earth will turn into a new planet, unsuitable for human habitation.
Now about another danger. As soon as Russia and the United States emerged from the Cold War stage, a new threat appeared. If you have heard about who Kim Jong Il is, then you understand that he will not stop there. This missile lover, tyrant and ruler of North Korea all rolled into one could easily provoke a nuclear conflict. He talks about the hydrogen bomb constantly and notes that his part of the country already has warheads. Fortunately, no one has seen them live yet. Russia, America, as well as its closest neighbors - South Korea and Japan, are very concerned even about such hypothetical statements. Therefore, we hope that North Korea’s developments and technologies will not be at a sufficient level for a long time to destroy the entire world.
For reference. At the bottom of the world's oceans lie dozens of bombs that were lost during transportation. And in Chernobyl, which is not so far from us, huge reserves of uranium are still stored.
It is worth considering whether such consequences can be allowed for the sake of testing a hydrogen bomb. And if a global conflict occurs between the countries possessing these weapons, there will be no states, no people, or anything at all left on the planet, the Earth will turn into a blank slate. And if we consider how a nuclear bomb differs from a thermonuclear bomb, the main point is the amount of destruction, as well as the subsequent effect.
Now a small conclusion. We figured out that a nuclear bomb and an atomic bomb are one and the same. It is also the basis for a thermonuclear warhead. But using neither one nor the other is not recommended, even for testing. The sound of the explosion and what the aftermath looks like is not the worst thing. This threatens a nuclear winter, the death of hundreds of thousands of inhabitants at once and numerous consequences for humanity. Although there are differences between charges such as an atomic bomb and a nuclear bomb, the effect of both is destructive for all living things.
Our article is devoted to the history of creation and general principles of synthesis of such a device, sometimes called hydrogen. Instead of releasing explosive energy by splitting the nuclei of heavy elements like uranium, it generates even more energy by fusing the nuclei of light elements (such as isotopes of hydrogen) into one heavy one (such as helium).
Why is nuclear fusion preferable?
During a thermonuclear reaction, which consists in the fusion of the nuclei of the chemical elements participating in it, significantly more energy is generated per unit mass of a physical device than in a pure atomic bomb that implements a nuclear fission reaction.
In an atomic bomb, fissile nuclear fuel quickly, under the influence of the energy of detonation of conventional explosives, combines in a small spherical volume, where its so-called critical mass is created, and the fission reaction begins. In this case, many neutrons released from fissile nuclei will cause the fission of other nuclei in the fuel mass, which also release additional neutrons, leading to a chain reaction. It covers no more than 20% of the fuel before the bomb explodes, or perhaps much less if conditions are not ideal: as in the atomic bombs Little Kid dropped on Hiroshima and Fat Man that hit Nagasaki, efficiency (if such a term can be applied to them) apply) were only 1.38% and 13%, respectively.
The fusion (or fusion) of nuclei covers the entire mass of the bomb charge and lasts as long as neutrons can find thermonuclear fuel that has not yet reacted. Therefore, the mass and explosive power of such a bomb are theoretically unlimited. Such a merger can theoretically continue indefinitely. Indeed, the thermonuclear bomb is one of the potential doomsday devices that could destroy all human life.
What is a nuclear fusion reaction?
The fuel for the thermonuclear fusion reaction is the hydrogen isotopes deuterium or tritium. The first differs from ordinary hydrogen in that its nucleus, in addition to one proton, also contains a neutron, and the tritium nucleus already has two neutrons. In natural water, there is one deuterium atom for every 7,000 hydrogen atoms, but from its quantity. contained in a glass of water, as a result of a thermonuclear reaction, the same amount of heat can be obtained as from the combustion of 200 liters of gasoline. At a 1946 meeting with politicians, the father of the American hydrogen bomb, Edward Teller, emphasized that deuterium provides more energy per gram of weight than uranium or plutonium, but costs twenty cents per gram compared with several hundred dollars per gram of fission fuel. Tritium does not occur in nature in a free state at all, so it is much more expensive than deuterium, with a market price of tens of thousands of dollars per gram, but the greatest amount of energy is released precisely in the fusion reaction of deuterium and tritium nuclei, in which the nucleus of a helium atom is formed and released neutron carrying away excess energy of 17.59 MeV
D + T → 4 He + n + 17.59 MeV.
This reaction is shown schematically in the figure below.
Is it a lot or a little? As you know, everything is learned by comparison. So, the energy of 1 MeV is approximately 2.3 million times more than that released during the combustion of 1 kg of oil. Consequently, the fusion of only two nuclei of deuterium and tritium releases as much energy as is released during the combustion of 2.3∙10 6 ∙17.59 = 40.5∙10 6 kg of oil. But we are talking about only two atoms. You can imagine how high the stakes were in the second half of the 40s of the last century, when work began in the USA and the USSR, which resulted in a thermonuclear bomb.
How it all began
As early as the summer of 1942, at the beginning of the atomic bomb project in the United States (the Manhattan Project) and later in a similar Soviet program, long before a bomb based on the fission of uranium nuclei was built, the attention of some participants in these programs was drawn to the device, which can use a much more powerful nuclear fusion reaction. In the USA, a supporter of this approach, and even, one might say, its apologist, was the above-mentioned Edward Teller. In the USSR, this direction was developed by Andrei Sakharov, a future academician and dissident.
For Teller, his fascination with thermonuclear fusion during the years of creating the atomic bomb was rather a disservice. As a participant in the Manhattan Project, he persistently called for the redirection of funds to implement his own ideas, the goal of which was a hydrogen and thermonuclear bomb, which did not please the leadership and caused tension in relations. Since at that time the thermonuclear direction of research was not supported, after the creation of the atomic bomb Teller left the project and began teaching, as well as researching elementary particles.
However, the outbreak of the Cold War, and most of all the creation and successful testing of the Soviet atomic bomb in 1949, became a new chance for the ardent anti-communist Teller to realize his scientific ideas. He returns to the Los Alamos laboratory, where the atomic bomb was created, and, together with Stanislav Ulam and Cornelius Everett, begins calculations.
The principle of a thermonuclear bomb
In order for the nuclear fusion reaction to begin, the bomb charge must be instantly heated to a temperature of 50 million degrees. The thermonuclear bomb scheme proposed by Teller uses for this purpose the explosion of a small atomic bomb, which is located inside the hydrogen casing. It can be argued that there were three generations in the development of her project in the 40s of the last century:
- Teller's variation, known as the "classic super";
- more complex, but also more realistic designs of several concentric spheres;
- the final version of the Teller-Ulam design, which is the basis of all thermonuclear weapon systems operating today.
The thermonuclear bombs of the USSR, whose creation was pioneered by Andrei Sakharov, went through similar design stages. He, apparently, completely independently and independently of the Americans (which cannot be said about the Soviet atomic bomb, created by the joint efforts of scientists and intelligence officers working in the USA) went through all of the above design stages.
The first two generations had the property that they had a succession of interlocking "layers", each of which reinforced some aspect of the previous one, and in some cases feedback was established. There was no clear division between the primary atomic bomb and the secondary thermonuclear one. In contrast, the Teller-Ulam thermonuclear bomb diagram sharply distinguishes between a primary explosion, a secondary explosion, and, if necessary, an additional one.
The device of a thermonuclear bomb according to the Teller-Ulam principle
Many of its details still remain classified, but it is reasonably certain that all thermonuclear weapons currently available are based on the device created by Edward Telleros and Stanislaw Ulam, in which an atomic bomb (i.e. the primary charge) is used to generate radiation, compresses and heats fusion fuel. Andrei Sakharov in the Soviet Union apparently independently came up with a similar concept, which he called the "third idea."
The structure of a thermonuclear bomb in this version is shown schematically in the figure below.
It was cylindrical in shape, with a roughly spherical primary atomic bomb at one end. The secondary thermonuclear charge in the first, not yet industrial samples, was made of liquid deuterium; somewhat later it became solid from a chemical compound called lithium deuteride.
The fact is that industry has long used lithium hydride LiH for balloon-free hydrogen transportation. The developers of the bomb (this idea was first used in the USSR) simply proposed taking its isotope deuterium instead of ordinary hydrogen and combining it with lithium, since it is much easier to make a bomb with a solid thermonuclear charge.
The shape of the secondary charge was a cylinder placed in a container with a lead (or uranium) shell. Between the charges there is a neutron protection shield. The space between the walls of the container with thermonuclear fuel and the bomb body is filled with special plastic, usually polystyrene foam. The bomb body itself is made of steel or aluminum.
These shapes have changed in recent designs such as the one shown below.
In it, the primary charge is flattened, like a watermelon or an American football ball, and the secondary charge is spherical. Such shapes fit much more efficiently into the internal volume of conical missile warheads.
Thermonuclear explosion sequence
When a primary atomic bomb detonates, in the first moments of this process a powerful X-ray radiation (neutron flux) is generated, which is partially blocked by the neutron shield, and is reflected from the inner lining of the housing surrounding the secondary charge, so that the X-rays fall symmetrically across its entire length
During the initial stages of a thermonuclear reaction, neutrons from an atomic explosion are absorbed by a plastic filler to prevent the fuel from heating up too quickly.
X-rays initially cause the appearance of a dense plastic foam that fills the space between the housing and the secondary charge, which quickly turns into a plasma state that heats and compresses the secondary charge.
In addition, the X-rays evaporate the surface of the container surrounding the secondary charge. The substance of the container, evaporating symmetrically relative to this charge, acquires a certain impulse directed from its axis, and the layers of the secondary charge, according to the law of conservation of momentum, receive an impulse directed towards the axis of the device. The principle here is the same as in a rocket, only if you imagine that the rocket fuel scatters symmetrically from its axis, and the body is compressed inward.
As a result of such compression of thermonuclear fuel, its volume decreases thousands of times, and the temperature reaches the level at which the nuclear fusion reaction begins. A thermonuclear bomb explodes. The reaction is accompanied by the formation of tritium nuclei, which merge with deuterium nuclei initially present in the secondary charge.
The first secondary charges were built around a rod core of plutonium, informally called a "candle", which entered into a nuclear fission reaction, i.e., another, additional atomic explosion was carried out in order to further raise the temperature to ensure the start of the nuclear fusion reaction. It is now believed that more efficient compression systems have eliminated the "candle", allowing further miniaturization of bomb design.
Operation Ivy
This was the name given to the tests of American thermonuclear weapons in the Marshall Islands in 1952, during which the first thermonuclear bomb was detonated. It was called Ivy Mike and was built according to the Teller-Ulam standard design. Its secondary thermonuclear charge was placed in a cylindrical container, which was a thermally insulated Dewar flask with thermonuclear fuel in the form of liquid deuterium, along the axis of which a “candle” of 239-plutonium ran. The dewar, in turn, was covered with a layer of 238-uranium weighing more than 5 metric tons, which evaporated during the explosion, providing symmetrical compression of the thermonuclear fuel. The container containing the primary and secondary charges was housed in a steel casing 80 inches wide by 244 inches long with walls 10 to 12 inches thick, the largest example of wrought iron up to that time. The inner surface of the case was lined with sheets of lead and polyethylene to reflect radiation after the explosion of the primary charge and create plasma that heats the secondary charge. The entire device weighed 82 tons. A view of the device shortly before the explosion is shown in the photo below.
The first test of a thermonuclear bomb took place on October 31, 1952. The power of the explosion was 10.4 megatons. Attol Eniwetok, where it was produced, was completely destroyed. The moment of the explosion is shown in the photo below.
The USSR gives a symmetrical answer
The US thermonuclear championship did not last long. On August 12, 1953, the first Soviet thermonuclear bomb RDS-6, developed under the leadership of Andrei Sakharov and Yuli Khariton, was tested at the Semipalatinsk test site. From the description above, it becomes clear that the Americans at Enewetok did not explode the bomb itself, as a type of ready-to-use ammunition, but rather a laboratory device, cumbersome and very imperfect. Soviet scientists, despite the small power of only 400 kg, tested a completely finished ammunition with thermonuclear fuel in the form of solid lithium deuteride, and not liquid deuterium, like the Americans. By the way, it should be noted that only the 6 Li isotope is used in lithium deuteride (this is due to the peculiarities of thermonuclear reactions), and in nature it is mixed with the 7 Li isotope. Therefore, special production facilities were built to separate lithium isotopes and select only 6 Li.
Reaching Power Limit
What followed was a decade of continuous arms race, during which the power of thermonuclear munitions continually increased. Finally, on October 30, 1961, in the USSR over the Novaya Zemlya test site in the air at an altitude of about 4 km, the most powerful thermonuclear bomb that had ever been built and tested, known in the West as the “Tsar Bomba,” was exploded.
This three-stage munition was actually developed as a 101.5-megaton bomb, but the desire to reduce radioactive contamination of the area forced the developers to abandon the third stage with a yield of 50 megatons and reduce the design yield of the device to 51.5 megatons. At the same time, the power of the explosion of the primary atomic charge was 1.5 megatons, and the second thermonuclear stage was supposed to give another 50. The actual power of the explosion was up to 58 megatons. The appearance of the bomb is shown in the photo below.
Its consequences were impressive. Despite the very significant height of the explosion of 4000 m, the incredibly bright fireball with its lower edge almost reached the Earth, and with its upper edge it rose to a height of more than 4.5 km. The pressure below the burst point was six times higher than the peak pressure of the Hiroshima explosion. The flash of light was so bright that it was visible at a distance of 1000 kilometers, despite the cloudy weather. One of the test participants saw a bright flash through dark glasses and felt the effects of the thermal pulse even at a distance of 270 km. A photo of the moment of the explosion is shown below.
It was shown that the power of a thermonuclear charge really has no limitations. After all, it was enough to complete the third stage, and the calculated power would be achieved. But it is possible to increase the number of stages further, since the weight of the Tsar Bomba was no more than 27 tons. The appearance of this device is shown in the photo below.
After these tests, it became clear to many politicians and military men both in the USSR and in the USA that the limit of the nuclear arms race had been reached and it needed to be stopped.
Modern Russia inherited the nuclear arsenal of the USSR. Today, Russia's thermonuclear bombs continue to serve as a deterrent to those seeking global hegemony. Let's hope they only play their role as a deterrent and are never detonated.
The sun as a fusion reactor
It is well known that the temperature of the Sun, or more precisely its core, reaching 15,000,000 °K, is maintained due to the continuous occurrence of thermonuclear reactions. However, everything that we could glean from the previous text speaks of the explosive nature of such processes. Then why doesn't the Sun explode like a thermonuclear bomb?
The fact is that with a huge share of hydrogen in the solar mass, which reaches 71%, the share of its isotope deuterium, the nuclei of which can only participate in the thermonuclear fusion reaction, is negligible. The fact is that deuterium nuclei themselves are formed as a result of the merger of two hydrogen nuclei, and not just a merger, but with the decay of one of the protons into a neutron, positron and neutrino (so-called beta decay), which is a rare event. In this case, the resulting deuterium nuclei are distributed fairly evenly throughout the volume of the solar core. Therefore, with its enormous size and mass, individual and rare centers of thermonuclear reactions of relatively low power are, as it were, smeared throughout its entire core of the Sun. The heat released during these reactions is clearly not enough to instantly burn out all the deuterium in the Sun, but it is enough to heat it to a temperature that ensures life on Earth.
I realized that bombs rust. Even atomic ones. Although this expression should not be taken literally, this is the general meaning of what is happening. For a number of natural reasons, complex weapons lose their original properties over time to such an extent that very serious doubts arise about their operation, if it comes to that. A clear example of this is the current story with the American B61 thermonuclear bomb, the situation with which has become generally confusing and, in part, even comical in some places. Manufacturers of nuclear warheads on both sides of the ocean provide the same warranty period for their products - 30 years.
Since we are unlikely to be talking about a corporate conspiracy of monopolists, it is obvious that the problem is in the laws of physics. This is how the author describes it.
The US National Nuclear Security Administration (NNSA) posted on its website a message about the start of engineering preparations for the production of the modernized thermonuclear bomb B61-12, which is a further modification of the B61 “product” that entered the US arsenal from 1968 to the end of the 1990s and constitutes today, on a par with Tomahawk cruise missiles, the backbone of American tactical nuclear power. As NNSA head Frank Klotz noted, this will extend the life of the system by at least another 20 years, i.e. until approximately 2040 - 2045.
Is it any wonder that journalists immediately made a fuss about this? What about the recently adopted bill in the United States banning the development of new types of nuclear weapons? But what about the terms of the START III treaty? True, there were also those who tried to link Klotz’s statement with the Russian statement made back in 2011 about the start of large-scale work to modernize its nuclear arsenal. True, there was talk not so much about the creation of new warheads, but about the development of new carriers, for example, fifth-generation intercontinental ballistic missiles Rubezh and Sarmat, the Barguzin railway complex, the Bulava sea-based missile and the construction of eight submarine cruisers. Borey." But who cares about such subtleties now? Moreover, tactical nuclear weapons still do not fall under the terms of START III. And, by and large, everything listed has a very indirect relationship to the root cause of history. The original motive lies, as has already been said, primarily in the laws of physics.
The history of the B61 began in 1963 with the TX-61 project at the Los Alamos National Laboratory in New Mexico. Mathematical modeling of the implementation of the concept of using nuclear weapons that was dominant at that time showed that even after massive nuclear strikes with ballistic missile warheads, a mass of important and well-protected objects will remain on the battlefield, relying on which the enemy (we all well understand who they had in mind) will be able to continue waging the big war. The US Air Force needed a tactical tool to “target”, so to speak, buried control and communications bunkers, underground fuel storage facilities, or other sites such as the famous underground submarine base in Crimea, using low-yield above-ground nuclear explosions. Well, as small as “from 0.3 kilotons.” And up to 170 kilotons, but more on that below.
The product went into production in 1968 and received the official name B61. During the entire production period, in all modifications, the Americans churned out 3,155 of these bombs. And from this moment the current story itself begins, since today out of the entire three-thousand-strong arsenal, there are only 150 “strategic” and about 400 “tactical” bombs left, as well as about 200 more “tactical” items in storage in reserve. That's all. Where did the rest go? It’s quite appropriate to joke - they’re completely rusty - and it won’t be that much of a joke.
The B61 bomb is a thermonuclear bomb, or as they are not entirely correct, but often called hydrogen. Its destructive effect is based on the use of the nuclear fusion reaction of light elements into heavier ones (for example, producing one helium atom from two deuterium atoms), which releases a huge amount of energy. Theoretically, it is possible to launch such a reaction in liquid deuterium, but this is difficult from a design point of view. Although the first test explosions at the test site were carried out this way. But it was possible to obtain a product that could be delivered to the target by plane only thanks to the combination of a heavy isotope of hydrogen (deuterium) and an isotope of lithium with a mass number of 6, known today as lithium deuteride -6. In addition to its “nuclear” properties, its main advantage is that it is solid and allows deuterium to be stored at positive ambient temperatures. Actually, it was with the advent of affordable 6Li that the opportunity arose to put it into practice in the form of a weapon.
The American thermonuclear bomb is based on the Teller-Ulam principle. With a certain degree of convention, it can be imagined as a durable case, inside of which there is an initiating trigger and a container with thermonuclear fuel. The trigger, or in our opinion a detonator, is a small plutonium charge, the task of which is to create the initial conditions for starting a thermonuclear reaction - high temperature and pressure. The “thermonuclear container” contains lithium-6 deuteride and a plutonium rod located strictly along the longitudinal axis, which plays the role of a fuse for a thermonuclear reaction. The container itself (can be made of either uranium-238 or lead) is coated with boron compounds to protect the contents from premature heating by the neutron flow from the trigger. The accuracy of the relative position of the trigger and the container is extremely important, therefore, after assembling the product, the internal space is filled with special plastic that conducts radiation, but at the same time ensures reliable fixation during storage and before the detonation stage.
When the trigger is triggered, 80% of its energy is released in the form of a pulse of so-called soft X-rays, which is absorbed by the plastic and the shell of the “thermonuclear” container. As the process progresses, both are transformed into a high-temperature, high-pressure plasma that compresses the contents of the container to less than a thousandth of its original volume. Thus, the plutonium rod goes into a supercritical state, becoming the source of its own nuclear reaction. The destruction of plutonium nuclei creates a neutron flux, which, interacting with lithium-6 nuclei, releases tritium. It already interacts with deuterium and the same fusion reaction begins, releasing the main energy of the explosion.
A: Warhead before explosion; the first step is at the top, the second step is at the bottom. Both components of a thermonuclear bomb.
B: The explosive detonates the first stage, compressing the plutonium core to a supercritical state and initiating a fission chain reaction.
C: During the cleavage process, the first stage produces a pulse of X-ray radiation that travels along the inside of the shell, penetrating the polystyrene foam core.
D: The second stage contracts due to ablation (evaporation) under the influence of X-rays, and the plutonium rod inside the second stage goes into a supercritical state, initiating a chain reaction, releasing enormous amounts of heat.
E: In compressed and heated lithium-6 deuteride, a fusion reaction occurs, the emitted neutron flux initiates the tamper splitting reaction. The fireball expands...
Well, until it all goes boom, the thermonuclear B61 is a familiar-looking “bomb-shaped piece of iron” with a length of 3.58 meters and a diameter of 33 cm, consisting of several parts. The nose cone contains control electronics. Behind it is a compartment with a charge that looks like a completely inconspicuous metal cylinder. Then there is a relatively small compartment with electronics and a tail with rigidly fixed stabilizers, containing a braking stabilizing parachute to slow down the speed of fall so that the plane that dropped the bomb has time to leave the area affected by the explosion.
Bomb “B-61” disassembled.
In this form, the bomb was stored “where it was needed.” Including almost 200 units deployed in Europe: in Belgium, the Netherlands, Germany, Italy and Turkey. Or do you think why the United States is recalling its citizens from Turkey today, even the families of diplomats are being evacuated, and the security at the Incirlik NATO airbase has occupied the perimeter “in a combative manner” and is actually preparing to shoot at its partner in the military bloc at the slightest attempt to cross the perimeter of the “American” sector? The reason is precisely the presence of some operational stock of American tactical nuclear weapons there. These are exactly the B61. It was not possible to establish exactly how many of them there are in Turkey, but there are 12 of them at the Ramstein airbase in Germany.
Field tests of the B61 first models generally gave satisfactory results. From a distance of 40 - 45 kilometers, the product fell into a circle with a radius of about 180 meters, which, with a maximum explosion power of 170 kilotons, guaranteed successful compensation of the miss in distance by the force of the ground explosion itself. True, the military soon drew attention to the theoretical possibility of the design to slightly vary the detonation power, since the maximum was not always required, and in a number of cases, excessive zeal caused much more harm than good. So the “pure” B61, as it was originally invented, no longer survives today.
The entire released stock went through a whole series of successive modifications, of which the most “ancient” is now B61-3 and soon followed by B61-4. The latter is especially interesting because the same product, depending on the electronics settings, can create an explosion with a power of 0.3 - 1.5 - 10 - 45 kilotons. Apparently, 0.3 kilotons is the approximate value of the explosion power of the trigger, without launching the subsequent thermonuclear part of the bomb.
Currently in service with the United States are the 3rd and 4th models of the B61, for the so-called “low” bombing used by tactical aircraft: F-16, F-18, F-22, A-10, Tornado and Eurofighter. And modified to power levels of 60, 80 and 170 kilotons, modifications 7 and 11 are considered “high-altitude” and are included in the range of weapons of the B-2A and B-52N strategic bombers.
The story would have ended there if not for physics. It would seem that they made a bomb, put it in a special storage facility, set up guards, and began their routine service. Well, yes, in the early 70s, as a result of aviation emergencies with B-52s patrolling in the air, several troubles happened when several nuclear bombs were lost. Off the coast of Spain, searches break out from time to time to this day. The US Air Force never admitted exactly how many “products” they had that time “sank along with the wreckage of the aircraft.” It’s just that there were 3,155, and there are about a thousand left; this cannot be attributed to any kind of emergency. Where did the difference go?
For the sake of tediousness, I described in detail above the structure of the American tactical “yadrenbaton”. Without it, it would be difficult to understand the essence of the problem that the United States faces, and which they have tried to hide for at least the last 15 years. You remember, the bomb consists of a “tank with thermonuclear fuel” and a plutonium trigger - a lighter. There are no problems with tritium. Lithium-6 deuteride is a solid substance and quite stable in its characteristics. Conventional explosives, which make up the detonation sphere of the initial trigger initiator, certainly change their characteristics over time, but replacing them does not create any particular problem. But there are questions about plutonium.
Weapons-grade plutonium - it decays. Constant and unstoppable. The problem with the combat effectiveness of “old” plutonium charges is that over time the concentration of Plutonium 239 decreases. Due to alpha decay (Plutonium-239 nuclei “lose” alpha particles, which are the nuclei of the Helium atom), an admixture of Uranium is formed instead 235. Accordingly, the critical mass grows. For pure Plutonium 239 it is 11 kg (10 cm sphere), for uranium it is 47 kg (17 cm sphere). Uranium -235 also decays (this is the same as in the case of Plutonium-239, also alpha decay), contaminating the plutonium sphere with Thorium-231 and Helium. An admixture of plutonium 241 (and it is always there, albeit a fraction of a percent) with a half-life of 14 years, also decays (in this case there is already beta decay - Plutonium-241 “loses” an electron and a neutrino), giving Americium 241, which further worsens the critical indicators (Americium-241 decays in the alpha version to Neptunium-237 and all that aka Helium).
When I talked about rust, I wasn't really joking. Plutonium charges “age.” And it seems impossible to “update” them. Yes, theoretically, you can change the design of the initiator, melt 3 old balls, fuse 2 new ones from them... By increasing the mass taking into account the degradation of plutonium. However, “dirty” plutonium is unreliable. Even an enlarged “ball” may not reach a supercritical state when compressed during an explosion... And if suddenly, by some statistical whim, an increased content of Plutonium-240 is formed in the resulting ball (formed from 239 by neutron capture), then on the contrary, it can bang right on factory The critical value is 7% Plutonium-240, exceeding which can lead to the elegantly formulated “problem” - “premature detonation”.
Thus, we come to the conclusion that to renew the B61 fleet, the United States needs new, fresh plutonium initiators. But officially, breeder reactors in America were closed back in 1988. There are, of course, still accumulated reserves. In the Russian Federation, by 2007, 170 tons of weapons-grade plutonium had been accumulated, in the USA - 103 tons. Although these reserves are also “aging”. Plus, I remember the NASA article that the United States only has enough Plutonium-238 for a couple of RTGs. The Department of Energy promises NASA 1.5 kg of Plutonium-238 per year. “New Horizons” has a 220-watt RTG containing 11 kilograms. “Curiosity” - carries an RTG with 4.8 kg. Moreover, there are suggestions that this plutonium has already been purchased in Russia...
This lifts the veil of secrecy over the issue of the “mass drying out” of American tactical nuclear weapons. I suspect that they dismantled all the B61s produced before the early 80s of the 20th century, so to speak, in order to avoid “sudden accidents.” And also in view of the unknown: - will the product work as it should if, God forbid, it does come to its practical use? But now the deadline for the rest of the arsenal has begun to approach, and apparently the old tricks no longer work with it. Bombs need to be disassembled, but there is nothing left to make new ones in America. From the word - in general. Uranium enrichment technologies have been lost, the production of weapons-grade plutonium has now been stopped by mutual agreement between Russia and the United States, special reactors have been stopped. There are practically no specialists left. And, as it turned out, the United States no longer has the money to start these nuclear dances from the beginning in the required quantity. But it is impossible to abandon tactical nuclear weapons for a number of political reasons. And in general, in the United States, everyone, from politicians to military strategists, is too accustomed to having a tactical nuclear baton. Without her, they feel somehow uncomfortable, cold, scared and very lonely.
However, judging by information from open sources, the nuclear filling in the B61 has not completely “rotten” yet. The product will still work for 15 - 20 years. Another question is that you can forget about setting it to maximum power. Means what? So we need to figure out how the same bomb can be placed more accurately! Calculations using mathematical models have shown that by reducing the radius of the circle into which the product is guaranteed to fall to 30 meters, and ensuring not a ground, but an underground detonation of the warhead at a depth of at least 3 to 12 meters, the destructive force of the impact, due to the processes flowing in a dense soil environment, the result is the same, and the power of the explosion can be reduced up to 15 times. Roughly speaking, the same result is achieved with 17 kilotons, instead of 170. How to do this? Yes, elementary, Watson!
The Air Force has been using Joint Direct Attack Munition (JDAM) technology for nearly 20 years. Take an ordinary “dumb” (from English dumb) bomb.
A guidance kit is attached to it, including the use of GPS, the tail section is replaced from passive to actively steering according to commands from the on-board computer, and here you have a new, “smart” bomb, capable of hitting a target accurately. In addition, replacing the materials of some elements of the body and head fairing makes it possible to optimize the trajectory of the product meeting an obstacle so that, due to its own kinetic energy, it can penetrate into the ground to the required depth before the explosion. The technology was developed by the Boeing Corporation in 1997 under a joint order of the Air Force and Navy USA. During the “Second Iraq War,” there was a known case of a 500-kilogram JDAM hitting an Iraqi bunker located 18 meters underground. Moreover, the detonation of the warhead of the bomb itself occurred at the minus third level of the bunker, located another 12 meters below. No sooner said than done! The United States has a program to modernize all 400 “tactical” and 200 “spare” B61s into the latest B61-12 modernization. However, there are rumors that “high-rise” options will also fall under this program.
The photo from the test program clearly shows that the engineers went exactly this way. You should not pay attention to the shank sticking out behind the stabilizers. This is an attachment element to a test bench in a wind tunnel.
It is important to note that an insert has appeared in the central part of the product, in which low-power rocket engines are located, the exhaust of the nozzles of which provides the bomb with its own rotation along the longitudinal axis. In combination with a homing head and active rudders, the B61-12 can now glide at a range of up to 120 - 130 kilometers, allowing the carrier aircraft to drop it without entering the target's air defense zone.
On October 20, 2015, the US Air Force conducted a drop test of a sample of a new tactical thermonuclear bomb at a test site in Nevada, using an F-15E fighter-bomber as a carrier. Ammunition without a charge confidently hit a circle with a radius of 30 meters.
Regarding accuracy (QUO):
This means that formally the Americans managed (they have an expression) to grab God by the beard. Under the guise of “simply modernizing one very, very old product,” which, moreover, does not fall under any of the newly concluded agreements, the United States created a “nuclear awl” with increased range and accuracy. Taking into account the peculiarities of the physics of the shock wave of an underground explosion and the modernization of the warhead to 0.3 - 1.5 - 10 - 35 (according to other sources up to 50) kilotons, in penetrating mode the B61-12 can provide the same destruction as in a conventional ground explosion with a capacity of 750 to 1250 kilotons.
True, the flip side of success was... money and allies. Since 2010, the Pentagon has spent only $2 billion on the search for a solution, including throw tests at the test site, which is mere nonsense by American standards. True, a malicious question arises: what did they come up with that was so new, considering that the most expensive serial set of equipment for retrofitting a conventional high-explosive bomb of the GBU type, comparable in size and weight, costs only 75 thousand dollars? Well, okay, why look into someone else's pocket.
Another thing is that experts from NNSA themselves predict the cost of converting the entire current B61 ammunition in the amount of at least $8.1 billion by 2024. This is if nothing goes up in price anywhere by that time, which is an absolutely fantastic expectation for American military programs. Although... even if this budget is divided into 600 products intended for modernization, the calculator tells me that the money will be needed at least 13.5 million dollars apiece. How much more expensive is this, considering the retail price of a regular “bomb intelligence” kit?
However, there is a very non-zero probability that the entire B61-12 program will never be fully implemented. This amount has already caused serious dissatisfaction with the US Congress, which is seriously engaged in searching for opportunities to sequester expenses and reduce budget programs. Including defense. The Pentagon, of course, is fighting to the death. Under Secretary of Defense for Global Strategy Madeleine Creedon told a congressional hearing that “the impact of sequestration threatens to undermine [nuclear weapons modernization] efforts and further increase unplanned costs by extending development and production periods.” According to her, already in its current form, budget cuts have led to a postponement of the start of the B61 modernization program by about six months. Those. The start of serial production of the B61-12 has moved to the beginning of 2020.
On the other hand, the civil congressmen sitting on various control, monitoring and all sorts of budgetary and financial commissions have their own reasons for sequestration. The F-35 aircraft, considered as the main carrier of new thermonuclear bombs, still does not really fly. The program for its supply to the troops has once again been disrupted and it is unknown whether it will be implemented at all. European NATO partners are increasingly expressing concern about the danger of increasing the “tactical sophistication” of the modernized B61 and the inevitable “some kind of response from Russia.” And over the past few years, it has already managed to demonstrate its ability to fend off new threats in completely asymmetrical ways. No matter how it turns out that as a result of Moscow’s retaliatory measures, nuclear security in Europe, despite the sweet speeches of Washington, did not increase, but, on the contrary, did not decrease. They increasingly cling to the desire for a nuclear-free Europe. And they are not at all happy with the modernized thermonuclear bombs. Perhaps the new British Prime Minister, in her first speech upon taking office, promised something about nuclear deterrence. The rest, especially Germany, France and Italy, are not at all shy about declaring that tactical nuclear weapons can be of least help against their real problems with migrants and terrorist threats.
But the Pentagon still has nowhere to go. If you don’t modernize these bombs in the next 4 to 8 years, then “rust will eat up” half of the current ammunition... And after another five years, the issue of modernization may disappear by itself, so to speak, due to the disappearance of the item for modernization.
And, by the way, they have the same problems with filling the warheads of strategic nuclear weapons...
sources
H-BOMB
a weapon of great destructive power (on the order of megatons in TNT equivalent), the operating principle of which is based on the reaction of thermonuclear fusion of light nuclei. The source of explosion energy is processes similar to those occurring on the Sun and other stars.
Thermonuclear reactions. The interior of the Sun contains a gigantic amount of hydrogen, which is in a state of ultra-high compression at a temperature of approx. 15,000,000 K. At such high temperatures and plasma densities, hydrogen nuclei experience constant collisions with each other, some of which result in their fusion and ultimately the formation of heavier helium nuclei. Such reactions, called thermonuclear fusion, are accompanied by the release of enormous amounts of energy. According to the laws of physics, the energy release during thermonuclear fusion is due to the fact that during the formation of a heavier nucleus, part of the mass of the light nuclei included in its composition is converted into a colossal amount of energy. That is why the Sun, having a gigantic mass, loses approx. every day in the process of thermonuclear fusion. 100 billion tons of matter and releases energy, thanks to which life on Earth became possible.
Isotopes of hydrogen. The hydrogen atom is the simplest of all existing atoms. It consists of one proton, which is its nucleus, around which a single electron rotates. Careful studies of water (H2O) have shown that it contains negligible amounts of “heavy” water containing the “heavy isotope” of hydrogen - deuterium (2H). The deuterium nucleus consists of a proton and a neutron - a neutral particle with a mass close to a proton. There is a third isotope of hydrogen - tritium, whose nucleus contains one proton and two neutrons. Tritium is unstable and undergoes spontaneous radioactive decay, turning into an isotope of helium. Traces of tritium have been found in the Earth's atmosphere, where it is formed as a result of the interaction of cosmic rays with gas molecules that make up the air. Tritium is produced artificially in a nuclear reactor by irradiating the lithium-6 isotope with a stream of neutrons.
Development of the hydrogen bomb. Preliminary theoretical analysis has shown that thermonuclear fusion is most easily accomplished in a mixture of deuterium and tritium. Taking this as a basis, US scientists at the beginning of 1950 began implementing a project to create a hydrogen bomb (HB). The first tests of a model nuclear device were carried out at the Enewetak test site in the spring of 1951; thermonuclear fusion was only partial. Significant success was achieved on November 1, 1951 during the testing of a massive nuclear device, the explosion power of which was 4e8 Mt in TNT equivalent. The first hydrogen aerial bomb was detonated in the USSR on August 12, 1953, and on March 1, 1954, the Americans detonated a more powerful (approximately 15 Mt) aerial bomb on Bikini Atoll. Since then, both powers have carried out explosions of advanced megaton weapons. The explosion at Bikini Atoll was accompanied by the release of large amounts of radioactive substances. Some of them fell hundreds of kilometers from the explosion site on the Japanese fishing vessel Lucky Dragon, while others covered the island of Rongelap. Since thermonuclear fusion produces stable helium, the radioactivity from the explosion of a pure hydrogen bomb should be no more than that of an atomic detonator of a thermonuclear reaction. However, in the case under consideration, the predicted and actual radioactive fallout differed significantly in quantity and composition.
The mechanism of action of a hydrogen bomb. The sequence of processes occurring during the explosion of a hydrogen bomb can be represented as follows. First, the thermonuclear reaction initiator charge (a small atomic bomb) located inside the NB shell explodes, resulting in a neutron flash and creating the high temperature necessary to initiate thermonuclear fusion. Neutrons bombard an insert made of lithium deuteride - a compound of deuterium with lithium (a lithium isotope with mass number 6 is used). Lithium-6 is split into helium and tritium under the influence of neutrons. Thus, the atomic fuse creates the materials necessary for synthesis directly in the actual bomb itself. Then a thermonuclear reaction begins in a mixture of deuterium and tritium, the temperature inside the bomb rapidly increases, involving more and more hydrogen in the synthesis. With a further increase in temperature, a reaction between deuterium nuclei, characteristic of a pure hydrogen bomb, could begin. All reactions, of course, occur so quickly that they are perceived as instantaneous.
Fission, fusion, fission (superbomb). In fact, in a bomb, the sequence of processes described above ends at the stage of the reaction of deuterium with tritium. Further, the bomb designers chose not to use nuclear fusion, but nuclear fission. The fusion of deuterium and tritium nuclei produces helium and fast neutrons, the energy of which is high enough to cause nuclear fission of uranium-238 (the main isotope of uranium, much cheaper than the uranium-235 used in conventional atomic bombs). Fast neutrons split the atoms of the uranium shell of the superbomb. The fission of one ton of uranium creates energy equivalent to 18 Mt. Energy goes not only to explosion and heat generation. Each uranium nucleus splits into two highly radioactive "fragments". Fission products include 36 different chemical elements and nearly 200 radioactive isotopes. All this constitutes the radioactive fallout that accompanies superbomb explosions. Thanks to the unique design and the described mechanism of action, weapons of this type can be made as powerful as desired. It is much cheaper than atomic bombs of the same power.
Consequences of the explosion. Shock wave and thermal effect. The direct (primary) impact of a superbomb explosion is threefold. The most obvious direct impact is a shock wave of enormous intensity. The strength of its impact, depending on the power of the bomb, the height of the explosion above the surface of the earth and the nature of the terrain, decreases with distance from the epicenter of the explosion. The thermal impact of an explosion is determined by the same factors, but also depends on the transparency of the air - fog sharply reduces the distance at which a thermal flash can cause serious burns. According to calculations, during an explosion in the atmosphere of a 20-megaton bomb, people will remain alive in 50% of cases if they 1) take refuge in an underground reinforced concrete shelter at a distance of approximately 8 km from the epicenter of the explosion (E), 2) are in ordinary urban buildings at a distance of approx. . 15 km from EV, 3) found themselves in an open place at a distance of approx. 20 km from EV. In conditions of poor visibility and at a distance of at least 25 km, if the atmosphere is clear, for people in open areas, the likelihood of survival increases rapidly with distance from the epicenter; at a distance of 32 km its calculated value is more than 90%. The area over which the penetrating radiation generated during an explosion causes death is relatively small, even in the case of a high-power superbomb.
Fire ball. Depending on the composition and mass of flammable material involved in the fireball, giant self-sustaining firestorms can form and rage for many hours. However, the most dangerous (albeit secondary) consequence of the explosion is radioactive contamination of the environment.
Fallout. How they are formed.
When a bomb explodes, the resulting fireball is filled with a huge amount of radioactive particles. Typically, these particles are so small that once they reach the upper atmosphere, they can remain there for a long time. But if a fireball comes into contact with the surface of the Earth, it turns everything on it into hot dust and ash and draws them into a fiery tornado. In a whirlwind of flame, they mix and bind with radioactive particles. Radioactive dust, except the largest, does not settle immediately. Finer dust is carried away by the resulting cloud and gradually falls out as it moves with the wind. Directly at the site of the explosion, radioactive fallout can be extremely intense - mainly large dust settling on the ground. Hundreds of kilometers from the explosion site and at greater distances, small but still visible particles of ash fall to the ground. They often form a cover similar to fallen snow, deadly to anyone who happens to be nearby. Even smaller and invisible particles, before they settle on the ground, can wander in the atmosphere for months and even years, circling the globe many times. By the time they fall out, their radioactivity is significantly weakened. The most dangerous radiation remains strontium-90 with a half-life of 28 years. Its loss is clearly observed throughout the world. When it settles on leaves and grass, it enters food chains that include humans. As a consequence of this, noticeable, although not yet dangerous, amounts of strontium-90 have been found in the bones of residents of most countries. The accumulation of strontium-90 in human bones is very dangerous in the long term, as it leads to the formation of malignant bone tumors.
Long-term contamination of the area with radioactive fallout. In the event of hostilities, the use of a hydrogen bomb will lead to immediate radioactive contamination of an area within a radius of approx. 100 km from the epicenter of the explosion. If a superbomb explodes, an area of tens of thousands of square kilometers will be contaminated. Such a huge area of destruction with a single bomb makes it a completely new type of weapon. Even if the superbomb does not hit the target, i.e. will not hit the object with shock-thermal effects, the penetrating radiation and radioactive fallout accompanying the explosion will make the surrounding space uninhabitable. Such precipitation can continue for many days, weeks and even months. Depending on their quantity, the intensity of radiation can reach deadly levels. A relatively small number of superbombs is enough to completely cover a large country with a layer of radioactive dust that is deadly to all living things. Thus, the creation of the superbomb marked the beginning of an era when it became possible to make entire continents uninhabitable. Even long after the cessation of direct exposure to radioactive fallout, the danger due to the high radiotoxicity of isotopes such as strontium-90 will remain. With food grown on soils contaminated with this isotope, radioactivity will enter the human body.
see also
NUCLEAR fusion;
NUCLEAR WEAPON ;
NUCLEAR WAR.
LITERATURE
Effect of nuclear weapons. M., 1960 Nuclear explosion in space, on earth and underground. M., 1970
Collier's Encyclopedia. - Open Society. 2000 .
See what a "HYDROGEN BOMB" is in other dictionaries:
An outdated name for a nuclear bomb of great destructive power, the action of which is based on the use of energy released during the fusion reaction of light nuclei (see Thermonuclear reactions). The first hydrogen bomb was tested in the USSR (1953) ... Big Encyclopedic Dictionary
Thermonuclear weapon is a type of weapon of mass destruction, the destructive power of which is based on the use of the energy of the reaction of nuclear fusion of light elements into heavier ones (for example, the synthesis of two nuclei of deuterium (heavy hydrogen) atoms into one ... ... Wikipedia
A nuclear bomb of great destructive power, the action of which is based on the use of energy released during the fusion reaction of light nuclei (see Thermonuclear reactions). The first thermonuclear charge (3 Mt power) was detonated on November 1, 1952 in the USA.… … encyclopedic Dictionary
H-bomb- vandenilinė bomba statusas T sritis chemija apibrėžtis Termobranduolinė bomba, kurios užtaisas – deuteris ir tritis. atitikmenys: engl. Hbomb; hydrogen bomb rus. hydrogen bomb ryšiai: sinonimas – H bomba… Chemijos terminų aiškinamasis žodynas
H-bomb- vandenilinė bomba statusas T sritis fizika atitikmenys: engl. hydrogen bomb vok. Wasserstoffbombe, f rus. hydrogen bomb, f pranc. bombe à hydrogène, f … Fizikos terminų žodynas
H-bomb- vandenilinė bomba statusas T sritis ekologija ir aplinkotyra apibrėžtis Bomba, kurios branduolinis užtaisas – vandenilio izotopai: deuteris ir tritis. atitikmenys: engl. Hbomb; hydrogen bomb vok. Wasserstoffbombe, f rus. hydrogen bomb, f... Ekologijos terminų aiškinamasis žodynas
An explosive bomb with great destructive power. Action V. b. based on thermonuclear reaction. See Nuclear weapons... Great Soviet Encyclopedia
