This page has been robot translated, sorry for typos if any. Original content here.

How the hydrogen bomb works

Как работает водородная бомба

A thermonuclear weapon (hydrogen bomb) is a type of nuclear weapon whose destructive force is based on using the energy of the reaction of nuclear synthesis of light elements into heavier ones (for example, the synthesis of one nucleus of a helium atom from two nuclei of deuterium atoms), in which a tremendous amount of energy is released.

Having the same damaging factors as nuclear weapons, thermonuclear weapons have a much greater possible explosion power (theoretically, it is limited only by the number of components available). It should be noted that the often cited assertion that radioactive contamination from a thermonuclear explosion is much weaker than from an atomic one, concerns fusion reactions that are used only in conjunction with much more "dirty" fission reactions. The term "clean weapon", which appeared in English literature, was out of use by the end of the 1970s. In fact, it all depends on the type of reaction used in a given product. So, the inclusion of elements from uranium-238 in the thermonuclear charge (in this case, the used uranium-238 is fused by fast neutrons and produces radioactive fragments. The neutrons themselves produce induced radioactivity) can significantly (up to five times) increase the total explosion power, but also significantly ( 5-10 times) increases the amount of radioactive fallout.

Everyone heard the unpleasant news of December - the successful testing of the hydrogen bomb by North Korea was completed. Kim Jong-un did not fail to hint (directly state) that he was ready at any moment to turn the weapon from defensive to offensive, which caused unprecedented excitement in the press of the whole world. However, there were optimists who declared the falsification of the tests: they say that the shadow from the Juche falls in the wrong place, and something is not visible radioactive fallout. But why is the aggressor’s presence of a hydrogen bomb such a significant factor for free countries, because even the nuclear warheads that North Korea has in abundance have never scared anyone like that?

general description

A thermonuclear explosive device can be built using either liquid deuterium or gaseous compressed. But the appearance of thermonuclear weapons became possible only thanks to a variety of lithium hydride - lithium-6 deuteride. This is a compound of the heavy hydrogen isotope - deuterium and lithium isotope with a mass number of 6.

Lithium-6 deuteride is a solid substance that allows you to store deuterium (the normal state of which under normal conditions is gas) at positive temperatures, and in addition, its second component, lithium-6, is the raw material for obtaining the most scarce hydrogen isotope - tritium. Actually, 6Li is the only industrial source of tritium production:

Как работает водородная бомба

In early US thermonuclear munitions, natural lithium deuteride was also used, containing mainly the lithium isotope with a mass number of 7. It also serves as a source of tritium, but for this, the neutrons involved in the reaction must have an energy of 10 MeV and higher.

Thermonuclear ammunition exists both in the form of aerial bombs (hydrogen or thermonuclear bombs) and warheads for ballistic and cruise missiles.

The thermonuclear bomb, operating on the principle of the Teller-Ulam, consists of two stages: a trigger and a container with thermonuclear fuel.

A trigger is a small plutonium nuclear charge with amplification (Boosted fission weapon (Eng.) Russian) with a capacity of several kilotons. The purpose of the trigger is to create the necessary conditions for initiating a thermonuclear reaction - high temperature and pressure.

A thermonuclear fuel container is the main element of the bomb. Inside it is a thermonuclear fuel - lithium-6 deuteride - and a plutonium rod located along the axis of the container, which plays the role of a fusion of the thermonuclear reaction. The shell of the container can be made of both uranium-238 - a substance that is fissioned by fast neutrons (> 0.5 MeV) released during the synthesis reaction, and of lead. The container is covered with a layer of a neutron absorber (boron compounds) to protect thermonuclear fuel from premature heating by neutron fluxes after a trigger explosion. The coaxial trigger and container are poured with special plastic that conducts radiation from the trigger to the container and are placed in a bomb body made of steel or aluminum.

It is possible that the second stage is not in the form of a cylinder, but in the form of a sphere. The principle of operation is the same, but instead of a plutonium ignition rod, a plutonium hollow sphere is used that is located inside and interspersed with layers of lithium-6 deuteride. Nuclear tests of bombs with a spherical shape of the second stage showed greater efficiency than bombs using a cylindrical shape of the second stage.

Как работает водородная бомба
The fusion of deuterium and tritium nuclei

In the explosion of a trigger, 80% of the energy is released in the form of a powerful pulse of soft x-ray radiation, which is absorbed by the second-stage shell and plastic filler, which turns into a high-temperature plasma under high pressure. As a result of a sharp heating of the uranium (lead) shell, the substance of the shell is ablated and a reactive thrust appears, which, together with the pressures of light and plasma, compresses the second stage. At the same time, its volume decreases by several thousand times, and thermonuclear fuel is heated to huge temperatures. However, the pressure and temperature are still insufficient to start the thermonuclear reaction; the creation of the necessary conditions is ensured by the plutonium rod, which, as a result of compression, goes into the supercritical state - a nuclear reaction begins inside the container. The neutrons emitted by a plutonium rod as a result of fission of plutonium nuclei interact with lithium-6 nuclei, resulting in tritium, which then interacts with deuterium.

How the hydrogen bomb works
  • A warhead before an explosion; the first step above, the second step below. Both components of a thermonuclear bomb.
  • B An explosive substance undermines the first stage by compressing the plutonium core to a supercritical state and initiating a chain fission reaction.
  • C In the process of splitting, an X-ray pulse occurs in the first stage, which propagates along the inner part of the shell, penetrating through the expanded polystyrene filler.
  • D The second stage is compressed due to ablation (evaporation) due to x-ray radiation, and the plutonium rod inside the second stage goes into a supercritical state, initiating a chain reaction, generating a huge amount of heat.
  • E In a compressed and heated lithium-6 deuteride, a fusion reaction occurs, the emitted neutron flux initiates the tamper fission reaction. The ball of fire expands ...

If the shell of the container was made of natural uranium, then fast neutrons formed as a result of the synthesis reaction cause fission reactions of uranium-238 atoms in it, adding their energy to the total energy of the explosion. A thermonuclear explosion of almost unlimited power is created in this way, since other layers of lithium deuteride and layers of uranium-238 (puff) can also be located behind the shell.

What is a hydrogen bomb

Как работает водородная бомба

The hydrogen bomb, also known as the Hydrogen Bomb or HB, is a weapon of incredible destructive power, whose power is measured in megatons in TNT. The principle of action of HB is based on the energy that is produced by thermonuclear fusion of hydrogen nuclei - exactly the same process takes place on the Sun.

How is a hydrogen bomb different from an atomic bomb

Как работает водородная бомба

Thermonuclear fusion - the process that occurs during the detonation of a hydrogen bomb - is the most powerful type of energy available to humanity. For peaceful purposes, we have not yet learned how to use it, but we have adapted it to the military. This thermonuclear reaction, similar to the one seen on stars, releases an incredible stream of energy. In atomic energy, however, is obtained from fission of the atomic nucleus, so the explosion of an atomic bomb is much weaker.

First test

And the Soviet Union again ahead of many participants in the Cold War race. The first hydrogen bomb, made under the leadership of the brilliant Sakharov, was tested at the secret training ground of Semipalatinsk - and they, to put it mildly, impressed not only scientists, but also western scouts.

Shock wave

Как работает водородная бомба

The direct destructive effect of the hydrogen bomb is the strongest, highly intense shock wave. Its power depends on the size of the bomb itself and the height at which the detonation of the charge occurred.

Thermal effect

Как работает водородная бомба

A hydrogen bomb of only 20 megatons (the largest bomb tested so far is 58 megatons) creates a huge amount of thermal energy: concrete melted within a radius of five kilometers from the site of the test shell. In a nine-kilometer radius all living things will be destroyed, neither equipment nor buildings will stand. The diameter of the funnel formed by the explosion will exceed two kilometers, and its depth will fluctuate around fifty meters.

Fire ball

Как работает водородная бомба

The most spectacular after the explosion will seem to observers a huge fireball: blazing storms initiated by the detonation of a hydrogen bomb will support themselves, drawing more and more combustible material into the funnel.

Radiation contamination

Как работает водородная бомба

But the most dangerous consequence of the explosion will, of course, be radiation contamination. The decay of heavy elements in a raging fire vortex will fill the atmosphere with the smallest particles of radioactive dust - it is so light that when it enters the atmosphere, it can circumnavigate the globe two or three times and only then will precipitate. Thus, one bomb explosion of 100 megatons could have consequences for the entire planet.

Tsar bomb

58 megatons - that’s how much the largest hydrogen bomb weighed at the training ground of the Novaya Zemlya archipelago weighed. The shock wave three times circled the globe, forcing the opponents of the USSR once again to assure themselves of the enormous destructive power of these weapons. Veselchak Khrushchev joked at the plenum that the bomb was no longer made only out of fear of breaking windows in the Kremlin.