Nuclear weapon. Nuclear weapons are explosive weapons of mass destruction based on the use of intranuclear energy

NUCLEAR WEAPONS, unlike conventional weapons, have a destructive effect due to nuclear, rather than mechanical or chemical energy.
In terms of the destructive power of the blast wave alone, one unit of nuclear weapon can exceed thousands of conventional bombs and artillery shells. In addition, a nuclear explosion has a destructive thermal and radiation effect on all living things, sometimes over large areas. Also on topic:

NUCLEAR WAR

Nuclear weapons tests were first carried out at the Alamogorda Air Force Base, located in the desert part of the state. New Mexico. The plutonium nuclear device, mounted on a steel tower, was successfully detonated on July 16, 1945. The energy of the explosion was approximately equal to 20 kt of TNT. The explosion created a mushroom cloud, turned the tower into steam, and melted the typical desert soil underneath into a highly radioactive glassy substance. (16 years after the explosion, the level of radioactivity in this place was still above normal.) Information about the successful experimental explosion was kept secret from the public, but was transferred to President Truman, who at that time was in Potsdam at negotiations on the post-war structure of Germany . W. Churchill and I. Stalin were also informed.

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H-BOMB

At this time, preparations were underway for the Allied invasion of Japan. To avoid an invasion and avoid the associated losses - hundreds of thousands of lives of Allied troops - on July 26, 1945, President Truman from Potsdam presented an ultimatum to Japan: either unconditional surrender or “quick and complete destruction.” The Japanese government did not respond to the ultimatum, and the president gave the order to drop the atomic bombs.

On August 6, a B-29 Enola Gay, taking off from a base in the Mariana Islands, dropped a uranium-235 bomb with a yield of approx. 20 kt. The large city consisted mainly of light wooden buildings, but there were also many reinforced concrete buildings. The bomb, which exploded at an altitude of 560 m, devastated an area of ​​approx. 10 sq. km. Almost all wooden buildings and many even the most durable houses were destroyed. The fires caused irreparable damage to the city. 140 thousand people out of the city's 255 thousand population were killed and wounded.

Even after this, the Japanese government did not make an unequivocal statement of surrender, and therefore on August 9 a second bomb was dropped, this time on Nagasaki. The loss of life, although not the same as in Hiroshima, was nevertheless enormous. The second bomb convinced the Japanese that resistance was impossible, and Emperor Hirohito took steps towards Japan's surrender.

In October 1945, President Truman legislated that nuclear research be transferred to civilian control. A bill passed in August 1946 established an Atomic Energy Commission of five members appointed by the President of the United States.

This commission ceased its activities on October 11, 1974, when President George Ford created the Nuclear Regulatory Commission and the Energy Research and Development Authority, with the latter being responsible for further development of nuclear weapons. In 1977, the US Department of Energy was created, which was supposed to oversee research and development in the field of nuclear weapons.

In 1956, the International Atomic Energy Agency (IAEA) was created. In 1970, when the Treaty on the Non-Proliferation of Nuclear Weapons was concluded, the IAEA took on an additional important function - to monitor the implementation of the said treaty by its parties that are not among the nuclear powers. Approximately one-third of the IAEA's resources go to activities related to such monitoring, and the other two-thirds to assistance and cooperation in energy development and security, as well as other peaceful nuclear programs.

In 1958, the European Atomic Energy Community (Euratom) was created, also to control the use of nuclear energy for peaceful purposes. Its original members were France, Italy, the Netherlands, Luxembourg and Germany. In 1973 it also included Great Britain, Ireland and Denmark, in 1981 – Greece, in 1986 – Spain and Portugal and in 1995 – Austria, Sweden and Finland.

POST-WAR WEAPONS DEVELOPMENT

After 1945, further development in the field of nuclear weapons went in two main directions: the improvement of weapons created during the Second World War and the creation of thermonuclear weapons.

The bomb exploded over Hiroshima was made of uranium-235, and in design it belonged to the so-called. gun type. In this type of bomb, the fissile material consists of two parts located at opposite ends of the gun barrel. The mass of each of these two halves is subcritical. One of them is called a target, the other is a projectile. For a bomb to explode, a non-nuclear explosive charge is detonated, causing the projectile to be fired at a target. A critical mass is formed, which leads to a nuclear explosion.

The implosion bomb dropped on Nagasaki requires less fissile material for a given explosion yield and is smaller in size; The power of the weapon can be changed according to the type of carrier. As a result of parallel developments, nuclear artillery shells were created.

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H-bomb.

Since the mass of each charge of uranium or plutonium in a bomb based on nuclear fission must be subcritical, the power of an atomic bomb can be increased only by increasing the number of charges. Thus, as the bomb's power increases, it quickly grows in size and eventually becomes untransportable. Therefore, researchers working in the field of nuclear weapons turned to the thermonuclear fusion reaction as a possible source of explosion energy (see also NUCLEAR FUNCTION). A thermonuclear (“hydrogen”) bomb can, in principle, be made of any size.

Corresponding research in the United States initially received almost no support, and until 1950 development and testing were practically non-existent. Only a few scientists, in particular E. Teller, continued to study this issue and improved the theory on which the tests could be based.

The Soviet Union detonated its first atomic bomb in 1949. President Truman on January 13, 1951 ordered the development of the hydrogen bomb to be accelerated. In November 1952, a non-transportable thermonuclear device was detonated in the United States. This was the first thermonuclear explosion; its power was several megatons of TNT equivalent. In 1953, the Soviet government announced the explosion of its thermonuclear bomb.

High radiation weapons.

High-radiation weapons are not inferior in penetrating radiation to the atomic (fission-based) weapons they are intended to replace, but they generate significantly less heat, create a weaker shock wave and less radioactive fallout. Such a “neutron bomb” (in fact, not a bomb, but an artillery shell), destroying manpower, is a tactical weapon designed for use against armored vehicles on small battlefields. The neutron bomb was tested in the United States, France, the Soviet Union, and probably the People's Republic of China, but apparently was not adopted for service. See also NUCLEUS FISSION; NUCLEAR FUSION.

TESTS

Nuclear tests are carried out for the purpose of general research of nuclear reactions, improvement of weapons technology, testing of new delivery systems, as well as the reliability and safety of methods for storing and servicing weapons. One of the main challenges when conducting testing is related to the need to ensure safety. Despite the importance of issues of protection from the direct effects of shock waves, heat and light radiation, the problem of radioactive fallout is still of paramount importance. So far, no “clean” nuclear weapons have been created that do not result in radioactive fallout.

Tests of nuclear weapons can be carried out in space, in the atmosphere, on water or on land, underground or under water. If they are carried out over land or over water, a cloud of fine radioactive dust is introduced into the atmosphere, which then disperses widely. When tested in the atmosphere, a zone of long-lasting residual radioactivity is formed. The United States, Great Britain and the Soviet Union abandoned atmospheric testing by ratifying the Three-Environment Nuclear Test Ban Treaty in 1963. France last carried out an atmospheric test in 1974. The most recent atmospheric test was carried out by the People's Republic of China in 1980. After that, all tests were carried out underground, and by France - under the ocean floor.

CONTRACTS AND AGREEMENTS

In 1958, the United States and the Soviet Union agreed to a moratorium on atmospheric testing. Nevertheless, the USSR resumed testing in 1961, and the USA in 1962. In 1963, the UN Disarmament Commission prepared a treaty banning nuclear tests in three environments: the atmosphere, outer space and under water. The treaty was ratified by the United States, the Soviet Union, Great Britain and over 100 other UN member states. (France and China did not sign it then.)

In 1968, the Treaty on the Non-Proliferation of Nuclear Weapons, also prepared by the UN Disarmament Commission, was opened for signing. By the mid-1990s, all five nuclear powers had ratified it, and a total of 181 states had signed it. The 13 non-signatories included Israel, India, Pakistan and Brazil. The Treaty on the Non-Proliferation of Nuclear Weapons prohibits all countries except the five nuclear powers (the UK, China, Russia, the United States and France) from possessing nuclear weapons. In 1995 this agreement was extended for an indefinite period.

Among the bilateral agreements concluded between the United States and the USSR were the Treaties on the Limitation of Strategic Arms (SALT I in 1972, SALT II in 1979), on the Limitation of Underground Testing of Nuclear Weapons (1974), and on Underground Nuclear Explosions for Peaceful Purposes (1976). .

In the late 1980s, the emphasis shifted from curbing arms growth and limiting nuclear testing to reducing the superpowers' nuclear arsenals. The Intermediate-Range Nuclear Forces Treaty, signed in 1987, committed both powers to eliminating their stockpiles of ground-launched nuclear missiles with a range of 500–5,500 km. Negotiations between the United States and the USSR on the reduction of offensive arms (START), conducted as a continuation of the SALT negotiations, ended in July 1991 with the conclusion of a treaty (START-1), under which both sides agreed to reduce their stockpiles of long-range nuclear ballistic missiles by approximately 30%. In May 1992, when the Soviet Union collapsed, the United States signed an agreement (the so-called Lisbon Protocol) with the former Soviet republics that owned nuclear weapons - Russia, Ukraine, Belarus and Kazakhstan - according to which all parties are obliged to implement the START treaty. 1. The START II treaty was also signed between Russia and the United States. It sets a limit on the number of warheads for each side, equal to 3500. The US Senate ratified this treaty in 1996.

The Antarctic Treaty of 1959 introduced the principle of a nuclear-free zone. Since 1967, the Treaty on the Prohibition of Nuclear Weapons in Latin America (Treaty of Tlatelolk), as well as the Treaty on the Peaceful Exploration and Use of Outer Space, came into force. Negotiations were also held about other nuclear-free zones.

DEVELOPMENTS IN OTHER COUNTRIES

The Soviet Union detonated its first atomic bomb in 1949 and a thermonuclear bomb in 1953. The USSR had tactical and strategic nuclear weapons in its arsenals, including advanced delivery systems. After the collapse of the USSR in December 1991, Russian President Boris Yeltsin began to ensure that nuclear weapons located in Ukraine, Belarus and Kazakhstan were transported for elimination or storage to Russia. In total, by June 1996, 2,700 warheads were rendered inoperable in Belarus, Kazakhstan and Ukraine, as well as 1,000 in Russia.

In 1952, Great Britain exploded its first atomic bomb, and in 1957, a hydrogen bomb. The country relies on a small strategic arsenal of submarine-launched ballistic missiles (SLBMs), as well as the use (until 1998) of airborne delivery vehicles.

France tested nuclear weapons in the Sahara Desert in 1960 and thermonuclear weapons in 1968. Until the early 1990s, France's tactical nuclear weapons arsenal consisted of short-range ballistic missiles and air-delivered nuclear bombs. France's strategic weapons include intermediate-range ballistic missiles and SLBMs, as well as nuclear bombers. In 1992, France suspended nuclear weapons tests, but resumed them in 1995 to modernize the warheads of submarine-launched missiles. In March 1996, the French government announced that the strategic ballistic missile launch site located on the Plateau d'Albion in central France would be phased out.

The PRC became the fifth nuclear power in 1964, and in 1967 it detonated a thermonuclear device. The PRC's strategic arsenal consists of nuclear bombers and intermediate-range ballistic missiles, and its tactical arsenal consists of intermediate-range ballistic missiles. In the early 1990s, China added submarine-launched ballistic missiles to its strategic arsenal. After April 1996, China remained the only nuclear power that did not stop nuclear testing.

Nuclear era. Part 10

Since the second half of the 20th century, nuclear weapons and nuclear energy have become an integral part of the cultural, military and technological spheres of human civilization. As nuclear technologies were mastered and new types of nuclear weapons were created, the attitude towards them changed among ordinary people, political and public figures, military men, scientists and engineers.

Having appeared as a “superweapon” in 1945 in the United States, the atomic bomb almost immediately turned into an instrument of political pressure on the Soviet Union. However, after the appearance of nuclear weapons in the USSR, the accumulation of stockpiles and the miniaturization of nuclear charges, they, along with the preservation of strategic objectives, began to be considered as a means of the battlefield. First, tactical missile systems and artillery shells with “nuclear filling” appeared in the USA, and then in the USSR. Anti-aircraft and aviation missiles, torpedoes and depth charges were equipped with nuclear warheads, and nuclear landmines were developed to create insurmountable obstacles in the path of enemy troops' advance.

Number of nuclear warheads in the USA and USSR/Russia

In the 60s of the last century, intercontinental ballistic missiles became the main means of solving strategic problems, replacing long-range bombers in this role. During the years of confrontation between the two world systems, the accumulation of the number of nuclear warheads and their delivery vehicles continued until the second half of the 80s. Their sharp reduction occurred after the collapse of the USSR and the formal end of the Cold War. However, the complete elimination of nuclear weapons, despite the predictions of some “idealistic humanists,” did not happen in the 21st century. Moreover, its role in ensuring the defense capability of our country during the years of decline and endless “reform” of the Russian army even increased. The presence of nuclear weapons in Russia largely kept our Western and Eastern “partners” from attempting to resolve political and territorial disputes by force. In addition to the strategic deterrent factor of the Russian nuclear triad, tactical nuclear weapons have played and continue to play a role, largely devaluing the superiority in the field of conventional weapons of NATO and the People's Liberation Army of China. It is no coincidence that the leadership of the United States has repeatedly raised the issue of Russian tactical nuclear weapons, proposing to publish data on their locations, exact quantitative and qualitative composition, as well as to conclude an agreement on the mutual elimination of tactical nuclear weapons.

Currently, in the world, official and unofficial members of the “nuclear club” have at their disposal an amount of fissionable and fissile materials sufficient to create 15,000 nuclear charges. About 5,000 nuclear warheads are quickly deployed on carriers, or can be prepared for use within a few days. According to estimates by the Federation of American Scientists, the Russian armed forces alone had approximately 1,800 deployed charges at the beginning of 2015. About 700 strategic warheads are stored in storage facilities separate from their carriers. The number of nuclear warheads awaiting their turn for disposal is estimated at 3,200 units. Although these warheads are largely no longer suitable for combat use, the nuclear materials they contain, after reprocessing, can be used to create new warheads. The US and Russian arsenals contain approximately 90% of the world's nuclear weapons.

A striking example of this are countries such as Iran and North Korea. If the Iranian nuclear program, at least formally, thanks to the efforts of international diplomacy, was able to be transferred to a peaceful plane, then North Korea, due to excessive pressure from the United States, Japan and South Korea, on the contrary, demonstrates intractability. Apparently, the fate of the leaders of Iraq and Libya, who at one time, for a number of reasons, refused to create their own nuclear weapons and ultimately became victims of aggression by Western countries, is a negative example for the leadership of the DPRK.

At different times, Argentina, Brazil, Libya and Sweden showed nuclear ambitions. These countries, at different stages of development of their own nuclear programs, abandoned the creation of an atomic bomb. Iraq was forced to stop developing nuclear weapons after the Israeli Air Force destroyed the Osirak nuclear reactor supplied from France.

Work on the creation of an atomic bomb in Argentina began in 1951 during the Perron dictatorship. Until the early 70s, four research reactors and a laboratory installation for radiochemical processing of irradiated nuclear fuel were put into operation. In 1973, about 1 kg of plutonium was produced, but for foreign policy reasons, plutonium production was stopped in 1974. At that time, Argentina already had the necessary scientific and technical base and production capacity for the production of heavy water, the production of nuclear fuel, uranium enrichment, radiochemical reprocessing of spent nuclear fuel and plutonium separation.

After the military government led by General Jorge Redondo came to power in 1978, it was officially announced that Argentina was developing atomic weapons. According to the then leadership of the country, the implementation of the national nuclear program should not only increase the prestige of Argentina, but also ensure national security in the context of competition with Brazil for regional leadership. During the implementation of the Argentine nuclear weapons program, plants were created to produce uranium dioxide, nuclear fuel and heavy water. However, after Argentina's defeat in the Falklands conflict, a civilian administration came to power, and the process of cooperation with Brazil and Argentina's inclusion in the international nuclear non-proliferation regime began. After Argentina and Brazil signed the Guadalajara Agreement on the use of atomic energy exclusively for peaceful purposes in 1991, the Argentine atomic weapons program was curtailed. After this, the Argentine leadership repeatedly declared that the creation of national nuclear weapons was contrary to the interests of the state, but the nuclear infrastructure and qualified personnel available in the country would allow this to be accomplished in a fairly short period of time.

For a fairly long period of time in Brazil, in parallel with peaceful nuclear research controlled by the IAEA, a secret nuclear weapons program was conducted since 1957. An additional incentive for the development of the Brazilian nuclear industry was the disclosure in 1983 of the completion of construction of a previously secret uranium enrichment plant in Argentina. In the early 80s, industrial uranium mining and enrichment began in Brazil. In 1986, uranium enriched to 20% was obtained. At the same time, a laboratory installation for extracting plutonium from spent nuclear fuel came into operation.

After the end of the period of military rule and the coming to power of a civilian administration, as in Argentina, in 1985, a gradual process began for Brazil to join the international nuclear non-proliferation regime. In the mid-90s, representatives of Brazil officially announced the existence of a nuclear weapons program in the 70–80s, codenamed Project Solimões. As part of this program, a 300-meter shaft was created to conduct nuclear tests in a remote area of ​​the country near Cachimbo (in the Amazon jungle), which was “officially” closed by Brazilian President F.C. de Melo September 17, 1990. At the time of the signing of the Guadalajara Agreement on the Use of Nuclear Energy Exclusively for Peaceful Purposes by Brazil and Argentina on July 18, 1991, representatives of the Air Force in Brazil had developed designs for two nuclear bombs with a design yield of 12 kt and 20–30 kt, but they were not assembled.

Just like neighboring Argentina, Brazil currently has the opportunity to create its own nuclear weapons in a fairly short time frame. In the municipality of Reseda (Rio de Janeiro), a uranium enrichment plant was launched in 2006. Its production capacity is sufficient to produce fuel assemblies for light water reactors with a capacity of 1000 MW, or to create approximately 30 uranium nuclear warheads per year. Brazilian specialists have the necessary qualifications and have proven nuclear technologies at their disposal for all key parts of the nuclear fuel cycle. If the country's leadership makes an appropriate decision, Brazil has the opportunity to relatively quickly begin producing highly enriched fissile materials with the subsequent production of nuclear explosive devices based on them.

Soon after coming to power in 1970, the leader of the Libyan revolution, M. Gaddafi, began to show nuclear ambitions. Since the country lacked the necessary scientific and industrial base, he turned to China and then to the USSR for help in creating an atomic bomb. But these appeals did not meet with understanding. Libya acceded to the NPT in 1975, after which the Soviet Union helped establish a research laboratory in 1977 and supplied a 10 MW light water research reactor along with highly enriched uranium in 1981.

But Libya could not create an atomic bomb on its own in the foreseeable future. Attempts to purchase a heavy water reactor, equipment for the production of heavy water, and a line for radiochemical processing of irradiated nuclear fuel in the USSR, despite the proposed $10 billion in the late 70s, were not successful. Due to US opposition, deals with Belgian and German companies were disrupted. As a result, Libya offered significant financial assistance to Pakistan in the hope of obtaining an “Islamic nuclear bomb.” Unable to purchase the necessary equipment and materials legally, Libya turned to nuclear technology. According to the confession of the “father” of the Pakistani nuclear bomb, Abdul Qadir Khan, through the illegal network created by him, 20 centrifuges for uranium enrichment and technical documentation on the design of a nuclear charge were delivered to Libya. At the same time, Libyan representatives carried out illegal purchases of uranium.

However, the weakness of Libya's scientific and technological base and international sanctions have prevented Libya from making serious progress in the production of weapons-grade fissile materials. In 2003, Libya, in exchange for a promise to lift sanctions, announced it would abandon its nuclear weapons program. The IAEA inspections that followed confirmed the absence of the possibility of producing weapons-grade nuclear materials in Libya. Existing special equipment and materials that violate the nonproliferation regime were removed from the country. We all know how this ultimately ended for M. Gaddafi.

Soon after the nuclear bombing of Japan, at the initiative of the military-political leadership of Sweden, research on nuclear topics began in the country. In 1946, all work in this area was concentrated at the Swedish National Defense Research Center. The original purpose of the research was to find out how Sweden could defend itself against attack by nuclear weapons. As a result, the leadership of the Swedish armed forces came to the conclusion that the best defense against aggression would be to have its own atomic bomb.

In the late 1940s, Sweden made a number of attempts to gain access to American nuclear secrets, including uranium enrichment technology, but was politely refused. After this, the Swedish leadership simply tried to buy ready-made nuclear warheads from the United States. In 1955, the estimated purchase volume was even announced - 25 nuclear bombs.

The Americans agreed to the meeting, but with two fundamental conditions. One of them was to maintain American control over Swedish nuclear charges, according to the other, Sweden was supposed to conclude a defense treaty with the United States and renounce neutrality. Both of these conditions were unacceptable to the Swedish government and the deal did not take place. After the failure of the nuclear agreement with the United States, the Swedish leadership decided to create an atomic bomb on its own. It must be said that Sweden had everything necessary for this - scientific, laboratory, production and raw material bases.

The Swedish Line national program for the production of nuclear weapons provided for the creation of 100 plutonium bombs weighing 400-500 kg and a yield of 20 kt. To achieve this, uranium enrichment plants were built in Kvarntorp and Ranstad, and the first heavy water nuclear reactor was launched in Stockholm in 1954. Heavy water for the reactor was imported from Norway.

After signing a bilateral agreement on cooperation with the United States in the field of civilian use of nuclear energy within the framework of the American Peaceful Atom program, the R-2 research reactor was delivered in 1956. In addition, Sweden now has the opportunity to access American research in the field of nuclear energy. Enriched uranium and heavy water began to arrive from the United States in small quantities at prices lower than from Norway. At the same time, the agreement specifically stipulated that Sweden could not use information and materials received from the Americans to create nuclear weapons.

In the 60s, nuclear research in Sweden advanced quite far, and the IBM 7090 semiconductor computer imported from the USA greatly helped in this. In 1964, the Agesta reactor, independently created in Sweden, began to operate. This reactor with a thermal power of 68 MW could produce up to 2 kg of plutonium per month, which already opened up real possibilities for the creation of nuclear weapons. It was planned to produce even larger volumes of plutonium at the reactor under construction in Marviken, but this reactor was never launched due to the refusal to create nuclear weapons.

In the second half of the 60s, Sweden's nuclear program advanced so much that it made it possible to produce the required amount of weapons-grade plutonium in a relatively short time and begin assembling nuclear explosive devices. By that time, using significant volumes of conventional explosives in the Nausta River basin, the nuclear testing technique had already been developed and a site for the construction of adits had been selected for underground testing on the Hjölen Highlands in Lapland. To begin assembling a nuclear charge and conducting tests, all that was needed was a political decision by the country’s leadership.

The Swedish government understood that the creation and maintenance of a nuclear arsenal would place a heavy burden on the economy. In addition, the country's nuclear status in the event of a conflict between NATO and the Warsaw Pact could lead to the Soviet Union launching a preventive nuclear strike on Sweden. In this regard, anti-nuclear protest sentiments grew in Sweden itself. Sweden acceded to the NPT in 1968 and ratified it on January 9, 1970. However, work on the weapons program was finally curtailed only in 1974. Recently, Sweden has not shown any interest in possessing nuclear weapons, but the country's scientific and production potential allows it to create quite modern types of nuclear weapons in a fairly short time.

The Iranian nuclear program deserves special mention. In the 50-60s of the last century, the Iranian Shah Reza Pahlavi made an attempt to rebuild life in the country in a European way. In 1957, Iran joined the American Atoms for Peace program and joined the IAEA. In 1967, a US-supplied research reactor began operating at the Tehran Nuclear Research Center. In the 1970s, Iran acquired technological equipment for uranium enrichment and the production of fuel cells and began implementing a nuclear energy program.

The Islamic Revolution of 1979 seriously slowed down work in this area; not only all foreign specialists, but also many Iranian physicists and engineers left the country. In the 80s, the Iranian nuclear program, which became weapons-oriented, began to be implemented with the help of the PRC and Pakistan. In the second half of the 80s, a nuclear research center began operating in Isfahan on the basis of a reactor supplied from China. However, the agreement concluded with China to build light water reactors there under US pressure was canceled.

In the 90s, Iran illegally received centrifuges for uranium enrichment and a package of technical documentation from Pakistan. The exact date of the start of uranium enrichment in Iran is not known, but at Fordo, near the city of Qom, a production line of approximately 2,000 centrifuges was operating in rock formations at a depth of 80-90 meters in 2012. IAEA inspectors discovered the first unaccounted Iranian centrifuges in Iran in 2004. After Mahmoud Ahmadinejad became president of the Islamic Republic of Iran in 2005, the country's position on nuclear issues became tougher. Iranian representatives at international negotiations insisted on the need to create a full complex for enrichment and reprocessing of spent nuclear fuel. Russia has taken the initiative to enrich Iranian uranium and process waste materials from the Bushehr nuclear power plant at its enterprises. This would exclude the possibility of extracting weapons-grade plutonium from spent fuel at nuclear power plants.

Google earth snapshot: Bushehr nuclear power plant

After international negotiations involving France, Germany and Great Britain, the USA, Russia and China reached a dead end, the UN Security Council adopted six resolutions demanding that Iran stop enriching and processing uranium, four of which provided for the introduction and tightening of sanctions against this country.

Despite the imposed international sanctions, Iran did not make concessions. Moreover, heavy water production facilities were commissioned in 2006, and in 2009 cooperation with the IAEA was limited and plans were announced to build ten new uranium enrichment facilities in the country. In 2010, Mahmoud Ahmadinejad announced that the first batch of uranium enriched to 20% had been received at the Natanz nuclear center, and that the country had the capacity to produce uranium with a higher degree of enrichment. In the second half of 2011, IAEA experts issued a conclusion that Iran was increasing its production capacity for uranium enrichment and was conducting work that could be interpreted as the production of nuclear weapons. In April 2013, Iran unveiled a 15-year program to build a cascade of 16 nuclear power plants.

By 2010, a complex of research and laboratory centers, factories for the extraction and enrichment of uranium was formed in Iran. Iran's nuclear industry is based on mines in Saganda and Gachina, uranium enrichment plants in Fordo and Erdekan, and nuclear centers in Esfahan, Tehran, Natanz and Parchin. According to IAEA estimates, Iran could have several uranium nuclear warheads by 2022 if the rate of uranium enrichment remains at the 2013 level.

Tensions surrounding Iran's nuclear program began to ease in late 2013, after Hassan Rouhani replaced Mahmoud Ahmadinejad as the country's president. At the negotiations in Geneva, it was possible to adopt a joint action plan, according to which Iran committed itself to stopping enriching uranium above 5% and destroying all stocks of nuclear materials enriched above this threshold, as well as stopping the construction of new uranium enrichment production facilities. In response, sanctions against Iran, which seriously hampered the development of the Iranian economy, were eased. The agreement for a period of six months came into force on January 20, 2014, and was subsequently extended twice - first until November 24, 2014, then until June 30, 2015. After inspections of Iranian nuclear facilities and a positive conclusion from the IAEA, international sanctions against Iran were lifted in January 2016.

Simultaneously with the nuclear program, a missile program was being implemented in Iran. The first ballistic missiles, which are North Korean copies of the Soviet R-17, appeared in Iran in the second half of the 80s. They were actively used at the final stage of the Iran-Iraq war to strike Iraqi cities. In the 90s, Iran's cooperation in the missile field with the DPRK continued. It was ballistic missiles that were supposed to become the main means of delivering Iranian nuclear weapons.

Based on missiles received from the DPRK, Iranian specialists have developed their own surface-to-surface missiles of the Shehab family. Thanks to the increased capacity of fuel and oxidizer tanks and the new North Korean engine, the Shehab-3 missile, which has been in service since 2003, has reached a flight range of 1100-1300 km with a warhead weight of 750-1000 kg.

Launch of the Iranian Shahab-3 ballistic missile

In August 2004, the modernized Shehab-3M MRBM was tested; Iranian specialists, by reducing the size of the missile warhead and increasing the power of its propulsion system and the capacity of the fuel tanks, achieved a launch range of 1,600 km. But the accuracy of these Iranian missiles is low (the COE is approximately 2.5 km); their effective combat use is only possible against such area targets as enemy cities. According to Israeli estimates, Iran has about 600 ballistic missiles of the Shehab family. They are placed both on mobile chassis and in camouflaged silos. At a military parade in September 2007, the Gadr-1 missile with a firing range of up to 2000 km was demonstrated. According to Iranian sources, it is a further development option for Shehab-3M.

The Safir launch vehicle was created using rocket propulsion systems running on Shehab liquid fuel; its third stage is solid fuel. On February 2, 2009, the improved Safir-2, launched from the Semnan missile site, launched the first Iranian satellite, Omid, into orbit.

Google Earth snapshot: Iranian missile site Semnan

In November 2008, the Sajil-1 solid-fuel single-stage MRBM was launched from the Semnan test site to a distance of about 2000 km. The two-stage Sajil-2 rocket demonstrated a launch range of 2,500 km in May 2009. Unlike Iranian medium-range liquid-propellant missiles, which require several hours of refueling and preparation to launch, Sajil solid-fuel missiles do not have this drawback. According to the Iranian military, it is planned to create mobile solid-fuel missile systems that will be constantly on combat patrol, thus, it is expected to carry out missile deterrence against Israel and guarantee the survival of Iranian IRBMs in the event of a sudden disarming strike.

Work on the creation of nuclear weapons was carried out at one time in Spain, Romania, Norway, Egypt, Saudi Arabia, Syria, Algeria, Myanmar, South Korea, Switzerland and Taiwan. After the collapse of the USSR, nuclear weapons remained in Ukraine, Belarus and Kazakhstan; according to the Lisbon Protocol signed in 1992, they were declared countries without nuclear weapons, and in 1994-1996 they transferred all nuclear weapons to Russia. In addition to the countries that have deliberately tried to create nuclear weapons, there are at least two dozen states in the world that are capable of creating their own nuclear weapons in the foreseeable future if they wish. First of all, these are European industrialized countries such as Germany, Italy, Belgium and the Netherlands, as well as Japan, Australia and Canada. Many countries have accumulated large reserves of plutonium extracted from spent nuclear fuel. For example, the reserves of fissile materials accumulated in Germany and Japan are sufficient to create more than a thousand nuclear weapons, which is comparable to the nuclear potential of Russia or the United States.

Nuclear proliferation data as of 2010

Despite the reduction in the number of nuclear warheads in Russia, the USA, France and Great Britain, the armed forces of states that have nuclear weapons regularly conduct training and exercises to practice preparation for the use of nuclear weapons and protection against them. In developed countries, where there are no nuclear weapons, they are preparing their army to operate in a nuclear war. Despite the declared end to the Cold War and the moratorium on nuclear testing, the improvement and creation of new types of nuclear weapons has not stopped. This is due to the fact that the military and political leadership of nuclear-weapon states are still considering possible nuclear war scenarios.

As sad as it may be, we must admit that nuclear war is possible. In the event of a global nuclear conflict between the United States and Russia, which will undoubtedly involve American NATO allies (including Great Britain and France), the parties could use up to 4,000 nuclear warheads against each other. This will have catastrophic consequences for the developed countries of the world. Over a short period of time, about 700 million people will die, and most of the industrial and infrastructural potential of “Western civilization” will be destroyed. However, as modern research shows, this will not lead to the death of life on the planet or even the complete destruction of humanity. The nuclear warheads at the disposal of the United States and Russia are enough to turn a country the size of France into a zone of complete destruction. But, apparently, a global “nuclear winter” will not occur, and radiation contamination of the area will not be as destructive as is commonly believed.

Without a doubt, the release of millions of tons of soot and dust into the atmosphere may have some effect on the amount of sunlight falling on the surface of the earth, this will briefly lower the temperature in temperate latitudes, but it will not be as significant as is generally believed in gloomy apocalyptic forecasts . The change in temperature in coastal and subtropical zones will be practically unnoticeable. This is confirmed by long-term observations of the consequences of large-scale forest fires and large volcanic eruptions, during which large volumes of solid particles are also released into the atmosphere. The bulk of soot during forest and man-made fires does not reach the stratosphere, and is rather quickly washed out of the lower layers of the atmosphere.

The idea that several thousand nuclear explosions could split the planet is also untenable. Since 1945, about 2,500 nuclear explosions have occurred on Earth, 12 of them with a power ranging from 10 to 58 Mt, but this did not lead to any global changes. During large volcanic eruptions, the amount of energy released exceeds the power of the bomb dropped on Hiroshima tens of times; in the 20th century alone there were more than 3,500 volcanic eruptions, but this did not have a noticeable effect on population growth on earth.

The greatest destructive effect of a nuclear explosion is achieved in the event of an air detonation of a nuclear charge. Modern nuclear warheads have a high utilization rate of fissile and fissionable materials, and in the absence of their contact with the ground during an air explosion, a minimal amount of radionuclides is formed, which subsequently fall out in the form of radioactive fallout. So, after testing a thermonuclear charge with a capacity of 58 Mt on Novaya Zemlya in 1961, the test participants arrived at the point above which the thermonuclear explosion occurred within two hours; the radiation level in this place did not pose a great danger. Currently, the radiation background in places where aerial nuclear test explosions were carried out differs little from natural values.

A nuclear explosion produces a complex mixture of more than 200 radioactive isotopes of 36 elements (from zinc to gadolinium), the most active being the short-lived radionuclides. Thus, 7, 49 and 343 days after the explosion, PYD activity decreases by 10, 100 and 1000 times, respectively, compared to the activity one hour after the explosion. In addition to nuclear fission products, radioactive contamination of the area is caused by radionuclides of induced activity and the scattered part of the nuclear charge that did not take part in the fission reaction. During airborne nuclear explosions, 20-25% of fission products fall out in the immediate vicinity. Some radionuclides are retained in the lower part of the atmosphere and, under the influence of wind, move over long distances, remaining at approximately the same latitude. They can remain in the air for about a month and gradually fall to Earth at a considerable distance from the point of explosion. The main part of the fission products formed during an air explosion is ejected into the stratosphere (to an altitude of 12-15 km), where they are globally dissipated and largely disintegrated. It is worth noting that in the event of a ground-based nuclear explosion, radiation contamination of the area can be tens of times greater. The greatest danger is posed by nuclear strikes on operating nuclear power plants and nuclear industry enterprises; in this case, radiation contamination of the area can actually have a catastrophic long-term character.

It is obvious that in the event of a global nuclear war, humanity, having suffered huge losses, will not disappear. It can be assumed that the centers of civilization after the “Third World War” will be the relatively underdeveloped countries of Asia, Africa, Central and South America, as well as Australia, unaffected by the nuclear conflict. Prophecies that the “Fourth World War” will be fought with “sticks and stones” are unfounded, since the accumulated knowledge and skills guarantee that humanity will maintain the technological path of development.

B61 nuclear bomb

In contrast to a global nuclear war, in the future during military conflicts it seems more likely that tactical nuclear weapons will be used. It is alarming that the improvement of nuclear weapons is leading to a lowering of the threshold for their use. Thus, the B61-12 nuclear bomb is currently being tested in the United States. After being adopted for service, this nuclear weapon should displace the majority of aerial bombs (except B61-11) of this family in service: B61-3, B61-4, B61-7, B61-10.

Thanks to the use of a satellite or inertial guidance system, the accuracy of B61-12 bombing should increase several times, which, according to the US military, along with the possibility of stepwise regulation of the explosion power (0.3, 5, 10, and 50 kt) will allow it to be used as a tactical , and strategic weapons. And also to minimize collateral damage from its use for one’s troops.

Another direction for improving nuclear weapons could be the creation of charges based on nuclear isomers, for example, a hafnium bomb based on hafnium-178m2. In terms of destructive effect, one gram of hafnium can be equivalent to 50 kilograms of TNT, and there is practically no radiation contamination of the area. However, research conducted at the US Defense Advanced Research Projects Agency from 1998 to 2004 showed that using current technologies, releasing excess energy from the hafnium-178m2 core is not yet possible. But one way or another, nuclear weapons have been in military arsenals for more than 70 years and their abandonment is not expected in the near future.

Based on materials: https://fas.org/issues/nuclear-weapons/status-world-nuclear-forces/ https://www.bellona.ru/reports/1174944248.53 https://warspot.ru/4658-neudavshayasya- kovka-molota-tora https://www.nationaldefense.ru/includes/periodics/armament/2012/0807/20358969/detail.shtml https://zver-v.livejournal.com/133575.html https://endoftheamericandream .com/archives/the-number-of-volcanoes-erupting-right-now-is-greater-than-the-20th-centurys-yearly-average

Proliferation of nuclear weapons.

In addition to those listed above, there are other countries that have the technology necessary to develop and create nuclear weapons, but those that have signed the Nuclear Non-Proliferation Treaty have abandoned the use of nuclear energy for military purposes. It is known that Israel, Pakistan and India, which have not signed the said treaty, have nuclear weapons. North Korea, which signed the treaty, is suspected of secretly carrying out work on the creation of nuclear weapons. In 1992, South Africa announced that it had six nuclear weapons in its possession, but that they had been destroyed, and ratified the Non-Proliferation Treaty. Inspections carried out by a special UN and IAEA commission in Iraq after the Gulf War (1990–1991) showed that Iraq had a serious nuclear, biological and chemical weapons program. As for its nuclear program, by the time of the Gulf War, Iraq was only two to three years away from developing ready-to-use nuclear weapons. The Israeli and US governments claim that Iran has its own nuclear weapons program. But Iran signed a non-proliferation treaty, and in 1994 an agreement with the IAEA on international control came into force. Since then, IAEA inspectors have not reported any evidence of nuclear weapons work in Iran.

History of the creation of weapons

The theoretical foundations for the military use of atomic decay were laid by the discovery of radioactivity by the Curie family (1898) and the work of E. Rutherford (1911). The Irishman E. Walton and the Englishman D. Cockroft (1932) in Cambridge were able to practically split the nucleus of an atom. At the English University of Birmingham, O. Frisch and R. Peierls (1939) theoretically calculated the critical mass of uranium required for a bomb explosion. It amounted to 10 kilograms of uranium -235. The USA and Germany began work on the construction of an atomic bomb almost simultaneously (August, September 1939). But Germany, which did not have its own reserves of uranium ore and was busy with military operations, could not give priority to nuclear weapons. W. Heisenberg's work on the construction of a nuclear reactor moved slowly. Of the five methods for separating isotopes, only one was effective. The practical experiment of obtaining a chain reaction (January 1945) was prevented by the dismantling of the equipment, which was carried out under the threat of the approach of Soviet troops.

American program

In the United States, not only American physicists worked on the nuclear program launched by a letter from L. Szilard, J. Wigner, and A. Einstein to the president. The works of German emigrant physicists Teller, Bethe, Bloch, Fuchs, and the Dane N. Bohr were used. The breakthrough moment of the project was the construction of the Los Alamos reactor under the leadership of Enrico Fermi, which made it possible to obtain weapons-grade plutonium and uranium. Before this, the Italian, who emigrated to the United States due to the persecution of Jews (1939), theoretically proved the moderation of neutrons, developed a uranium-graphite reactor circuit, and conducted practical experiments to obtain a self-sustaining chain reaction.

Enrico Fermi gives a lecture at the Chicago Institute for Nuclear Research

Such large-scale work as the creation of a completely new type of weapon is beyond the capabilities of one person or a small team of scientists. The American Manhattan Project employed more than 100,000 people, of which 40,000 were scientists, technicians, and female computer scientists. However, Americans consider Robert Oppenheimer the “father of the bomb.”

Robert Oppenheimer at a meeting of the US Senate committee

In the Los Alamos laboratory, Oppenheimer led the scientific part of the project, coordinated the work of scientists. General L. Groves, later the main initiator of the nuclear bombing of Japan, was responsible for the organization of construction, secrecy, and security. By the time he began working on the nuclear project, R. Oppenheimer was the author of a number of scientific papers on quantum transitions, gravitational collapse, calculation of the properties of mesons, and proof of the Ehrenfest-Oppenheimer theorem.

THIS IS INTERESTING. The results of the practical use of atomic weapons impressed R. Oppenheimer so much that he became an active opponent of the military use of the atom. The scientist's statements about the need to contain and limit the nuclear race led to Oppenheimer's removal from the secret programs of the United States (1954).

The raw material for obtaining uranium-235 was uranium ore from a Congolese mine of a Belgian company. The amount of ore exported to the United States before the mine was flooded was limited. It was not possible to use the technology for separating different isotopes of uranium using a centrifuge. To obtain pure uranium-235, which enters into a fission reaction, gas diffusion, electromagnetic separation, and thermal diffusion were used. By the planned date (summer 1945), there was only enough purified uranium-235 to equip one bomb, called “Baby”. For the “Malysh” demolition device, a cannon design was used, in which the critical mass of the charge was achieved by connecting two blocks of subcritical mass using a powder charge. The designers had no doubt that the cannon circuit would work, so tests of the only bomb were not carried out. There were no similar difficulties in the production of plutonium-239. It was obtained from uranium-238, of which enough had been accumulated. Plutonium charges were made for two bombs, called "Thing" and "Fat Man". But the cannon circuit for plutonium charges was unsuitable. The designers had to use an implosion detonation scheme, in which dozens of explosive lenses compressed fragments of weapons-grade plutonium to a critical mass.

First tests, practical use of nuclear weapons

The Americans conducted the first test of the shellless bomb “Thing” (July 16, 1945), which received the code “Trinity”, at the Alamogordo test site. A ground explosion of the device showed a power equal to the detonation of 21 thousand tons of TNT explosive. The lifeless, uninhabited desert of New Mexico was chosen for the test detonation. In addition to human casualties, several scientists feared the occurrence of an uncontrolled oxygen burning reaction in the Earth's atmosphere.

Explosion of "Things" in the Trinity Project

The temperature at the explosion site melted the quartz rocks into a green glassy mass called “trinitite.” Encouraged by the success, the US government ordered the preparation of nuclear weapons to be dropped on Japan. Uranium and plutonium charges were “dressed” in aerial bomb shells. At the same time, “Fat Man”, due to the implosion design of the detonation, was significantly larger in size and weight than “Kid”.

Models of “Fat Man” and “Kid” in the modern nuclear weapons museum

The bombs were equipped with barometric and time fuses, providing air detonation of the charge at an altitude of 500-700 meters. A separate aviation regiment, number 509 (since 1944), worked to service the nuclear project. It was the commander of this regiment, Paul Tibbetts, who carried out the order of the Secretary of War (endorsed by President Truman) to bomb Japan.

The crew of the Enola Gay. Colonel Paul Tibbetts in the center (with a pipe in his mouth)

On the night of August 6, a group of aircraft took off from an American air base in the Mariana Islands, consisting of the main B-29 bomber (number 44-86292, name “Enola Gay”), three reconnaissance aircraft, two aerial photography aircraft, and a reserve bomber. After 6 hours of flight, having flown about 2,500 miles, the group reached the shores of southern Japan. Scouts sent ahead reported no clouds over Hiroshima, the main target of the flight. At 8 a.m., Enola Gay, piloted by P. Tibbetts, dropped a uranium bomb over the center of Hiroshima. At the time of the bombing, up to 250 thousand people lived in Hiroshima, large military warehouses were based, the headquarters of Field Marshal S. Hata, commander of the defense of Southern Japan. As a result of the explosion (the power is estimated at 10–17 kilotons) from light radiation, a blast wave, and a fire tornado, up to 140 thousand Japanese died, the city burned out with a diameter of 2 kilometers.

Documentary photo of the destruction in Hiroshima

No less terrifying was the explosion of a plutonium charge over Nagasaki. “Fat Man” was dropped on a Japanese port by “B-29” under the command of Major C. Sweeney. Cloud cover did not allow the crew to aim accurately; the bomb was dropped over the hills and industrial area. Therefore, despite the high power (21 kilotons), the plutonium charge killed “only” 74 thousand Japanese. Subsequently, at least 450 thousand people died from radiation poisoning in Japan. The atomic bombings did not bring the immediate surrender of Japan, but pushed the USSR to declare war and begin the Manchurian operation. Only after the loss of the Kwantung Army (defeated in 10 days), the complete liberation of Manchuria and the north of Korea from Japanese troops, the emperor agreed to surrender (signed on September 2, 1945). But for some time, aggressive US military circles felt like a monopolist that could dictate terms to the whole world. American staff officers even developed plans for a “preemptive war” against the USSR. Military operations under the Trojan plan were to begin in 1950. The plan was later adjusted to 1957 to include NATO countries. Aggressive plans were stopped only by the first tests of Soviet nuclear weapons.

Soviet nuclear program

Until 1941, Soviet scientists were engaged in the theory of the structure of the atomic nucleus, chain reactions, and radiochemical research without going into the topic of nuclear weapons. All-Union conferences were held on nuclear physics; this topic was dealt with by the Leningrad Radium Institute, the First Phystech, and the Kharkov Institute of Physics and Technology. The first impetus for thoughts about the military use of atomic decay was the cessation of publications on nuclear physics in scientific journals in Germany, Great Britain, and the USA. The German physicist F. Lange, who emigrated to the USSR (1935), organized a shock stress laboratory at the Kharkov UPTI. Back in 1940, Lange and his laboratory employees V. Spinel and V. Maslov submitted to the People's Commissariat of Defense of the USSR a proposal to work on “uranium ammunition”, which did not receive support from the leadership. With the outbreak of war, nuclear research was reduced to a minimum, laboratories were closed or evacuated. By the end of 1941, intelligence reports appeared in the NKVD about the intensification of secret developments in atomic energy in the USA and Great Britain. Soviet intelligence copied the transcript of the English “MAUD Committee”, from which it was clear that British experts determined the real time frame for the creation of an atomic bomb to be 3-4 years. After this, nuclear research in the USSR was classified, and scientists were tasked with developing technologies for purifying uranium and developing weapons designs. In this program, methods of beta spectroscopy of nuclei were studied, nuclear fission under the influence of cosmic radiation was discovered, and a plutonium preparation was obtained in pulsed quantities. The complete technology for separating plutonium from irradiated uranium was developed by the Radium Institute (1946, director V. Khlopin). GIPH employees (N. Khovansky, Y. Zilberman) created the technological part for the construction of a radiochemical plant. The head of the Soviet atomic project was I.V. Kurchatov (March 1943). Before this appointment, the forty-year-old scientist:

• was invited by academician A. Ioffe to LPTI (1925);
• began studying atomic physics, headed the physics department, a special laboratory at the Leningrad Physics and Technology Institute (1930-1932);
• participates in the design and launch of the Leningrad cyclotron (1932-1937);
• studies the capture of a neutron by a proton, discovers selective absorption of neutrons, resonance phenomena of the process (in a team, 1935-1940);
• obtains nuclear constants for the fission reaction of uranium (1939);
• theoretically proves the possibility of a chain reaction of uranium and heavy water (1940);
• develops a system for demagnetizing ship hulls, introduces protection against magnetic mines in the Baltic and Black Sea fleets (1940-1941).

At the first stage of the project (1943-1945), Kurchatov’s “Laboratory No. 2” carried out research work, studied methods for producing metallic uranium and uranium carbide. For this work, Kurchatov achieved the demobilization of the necessary specialists from the army. After the American explosions, practical work accelerated sharply. An experimental reactor (based on a cyclotron transported from Leningrad) and a working reactor to produce weapons-grade plutonium were built (December 1946). To obtain uranium isotopes, the gas diffusion technique was used. Based on them, an industrial reactor started operating in the closed zone “Combine 817” (Ozersk, Chelyabinsk region) (June 1948). The Mayak plant began producing plutonium using acetate-precipitation technology and produced weapons-grade plutonium in the quantities required for the first test (1949). At the same time, fuses for bombs using polonium-beryllium sources were invented. Yu. Khariton became Kurchatov’s right hand in the atomic project. Under his scientific leadership, the secret KB-11 was built and put into operation in a closed area (Kremlin, Arzamas-75, Arzamas-16, Sarov, Nizhny Novgorod region).

Igor Vasilyevich Kurchatov and Yuliy Borisovich Khariton on vacation in Semipalatinsk

The chief designer of the classified KB-11 was busy designing a plutonium device, increasing power, and reducing the weight of a bomb copied from an American design (received from Soviet intelligence officers). At the same time, a number of new solutions were found that made it possible to double the original parameters of the American model. The third key point in the industrial production of ammunition was the assembly plant organized near Zarechny (Penza region). The object, referred to as Penza-19 according to secret documentation, was built on the basis of instrument-making plant No. 1134. In closed suburban areas, which were popularly called “Second Production”, “Equipment Base”, until 2002, all devices developed by Sarov and Snezhinsk (“Chelyabinsk-50”) were assembled.

Model of the RDS-2 aerial bomb in the Zarechny Museum

THIS IS INTERESTING. In Zarechny, on the basis of the Start production association, one of the three Russian nuclear weapons museums operates. Two other museums were opened in Sarov and Snezhinsk (the Arzamas-16 backup was built near Chelyabinsk in 1957). Tests of “RDS-1” (the code name for a ground-based device without an aircraft shell) were carried out at the Semipalatinsk test site in 1949. By the morning of August 29, the device was assembled. At 7 am, a command was given from the control panel to detonate a charge of 20 kilotons.

An authentic launchpad for a nuclear device during its first tests is demonstrated in the Sarov Museum

At the test site (170 kilometers from the regional center), a forty-meter steel tower was built. Several thousand instruments and radiation sensors were placed in concentric circles around the test site. Military fortifications and civilian facilities (residential buildings, concrete production workshops) were built along a ten-kilometer circle. Equipment was placed in positions - tanks, planes, guns. Sheep and goats were tied up in military shelters (trenches and dugouts). On the far side there are enclosures with experimental animals (rabbits, pigs, rats). All houses and bridges were destroyed or burned, as well as trucks. The shock wave overturned guns and tanks. Only the monolithic frames of reinforced concrete buildings survived.

EFFECT OF NUCLEAR EXPLOSION

Nuclear weapons are designed to destroy enemy personnel and military facilities. The most important damaging factors for people are shock wave, light radiation and penetrating radiation; the destructive effect on military targets is mainly due to the shock wave and secondary thermal effects.

When conventional explosives detonate, almost all the energy is released in the form of kinetic energy, which is almost completely converted into shock wave energy. In nuclear and thermonuclear explosions, the fission reaction is approx. 50% of all energy goes into shock wave energy, and approx. 35% - into light radiation. The remaining 15% of the energy is released in the form of various types of penetrating radiation.

During a nuclear explosion, a highly heated, luminous, approximately spherical mass is formed - the so-called.
fire ball. It immediately begins to expand, cool and rise. As it cools, the vapors in the fireball condense to form a cloud containing solid particles of bomb material and water droplets, giving it the appearance of a normal cloud. A strong air draft arises, sucking moving material from the surface of the earth into the atomic cloud. The cloud rises, but after a while it begins to slowly descend. Having dropped to a level at which its density is close to that of the surrounding air, the cloud expands, taking on a characteristic mushroom shape. Table 1. Effect of shock wave

Introduction

Nuclear weapons are weapons whose destructive action is based on the use of intranuclear energy released during a nuclear explosion.

Nuclear weapons are based on the use of intranuclear energy released during chain reactions of fission of heavy nuclei of the isotopes of uranium-235, plutonium-239 or during thermonuclear reactions of fusion of light nuclei - hydrogen isotopes (deuterium and tritium) into heavier ones. units

These weapons include a variety of nuclear warheads (missile and torpedo warheads, aircraft and depth charge warheads, artillery shells and mines) equipped with nuclear chargers, as well as the means to control them and deliver them to the target.

The main part of a nuclear weapon is a nuclear charge containing a nuclear explosive (NF) - uranium-235 or plutonium-239.

A nuclear chain reaction can only develop if there is a critical mass of fissile material.

Before the explosion, the nuclear explosive in one munition must be divided into separate parts, the mass of each of which must be less than the critical mass. To carry out an explosion, it is necessary to combine them into one, i.e. create a supercritical mass and initiate the start of the reaction from a special neutron source.

Direct energetic effect.

Shock wave action.

A split second after the explosion, a shock wave spreads from the fireball - like a moving wall of hot compressed air. The thickness of this shock wave is much greater than that of a conventional explosion, and therefore it affects the oncoming object longer. The pressure surge causes damage due to its entraining action, causing objects to roll, collapse and be thrown around. The strength of the shock wave is characterized by the excess pressure it creates, i.e. exceeding normal atmospheric pressure. At the same time, hollow structures are more easily destroyed than solid or reinforced ones. Squat and underground structures are less susceptible to the destructive effects of a shock wave than tall buildings. The human body has amazing resistance to shock waves. Therefore, the direct impact of the excess pressure of the shock wave does not lead to significant casualties. Most people die under the rubble of collapsing buildings and are injured by fast moving objects. In table Figure 1 shows a number of different objects, indicating the overpressure that causes serious damage and the radius of the zone in which serious damage is observed in explosions with yields of 5, 10 and 20 kt TNT equivalent.

Action of light radiation.

As soon as a fireball appears, it begins to emit light radiation, including infrared and ultraviolet. There are two flashes of light emission: an intense but short duration explosion, usually too short to cause significant casualties, and then a second, less intense but longer lasting one. The second outbreak is responsible for almost all human losses due to light radiation. Light radiation travels in a straight line and acts within the visibility of the fireball, but does not have any significant penetrating power. An opaque fabric, such as a tent fabric, can provide reliable protection against it, although the fabric itself can catch fire. Light-colored fabrics reflect light radiation and therefore require more radiation energy to ignite than dark ones. After the first flash of light, you can have time to hide behind one or another shelter from the second flash. The extent to which a person is damaged by light radiation depends on the extent to which the surface of his body is exposed. The direct action of light radiation usually does not lead to major damage to materials. But because such radiation causes fire, it can cause great damage through secondary effects, as evidenced by the colossal fires in Hiroshima and Nagasaki.

Penetrating radiation.

The initial radiation, consisting mainly of gamma rays and neutrons, is emitted by the explosion itself for about 60 s. It operates within line of sight. Its damaging effect can be reduced if, upon noticing the first explosive flash, you immediately hide in cover. The initial radiation is highly penetrating, so protection from it requires a thick sheet of metal or a thick layer of soil. A steel sheet 40 mm thick transmits half of the radiation incident on it. As a radiation absorber, steel is 4 times more effective than concrete, 5 times more effective than earth, 8 times more effective than water, and 16 times more effective than wood. But it is 3 times less effective than lead. Residual radiation is emitted for a long time. It may be associated with induced radioactivity and radioactive fallout. As a result of the action of the neutron component of the initial radiation on the ground near the epicenter of the explosion, the ground becomes radioactive. In explosions on the surface of the earth and at low altitudes, the induced radioactivity is especially high and can persist for a long time. “Radioactive fallout” refers to contamination by particles falling from a radioactive cloud. These are particles of fissile material from the bomb itself, as well as material drawn into the atomic cloud from the earth and becoming radioactive as a result of exposure to neutrons released during a nuclear reaction. Such particles gradually settle, which leads to radioactive contamination of surfaces. The heavier ones quickly settle near the explosion site. Lighter radioactive particles carried by the wind can settle over distances of many kilometers, contaminating large areas over a long period of time. Direct human losses from radioactive fallout can be significant near the epicenter of the explosion. But as the distance from the epicenter increases, the radiation intensity quickly decreases.

What is worth knowing about the lesions?

The size of the source depends on the power of the nuclear explosion. The characteristics of destruction in the source are directly dependent on the strength of structures and the number of storeys of buildings, as well as building density. If we talk about the outer boundary of a nuclear destruction, then it occupies a conventional line on the ground, which is drawn at a distance from the center of the explosion. The excess pressure of the shock wave has a value of 10 kPa.

The source of destruction of weapons of mass destruction is a zone that was influenced by the damaging factors of a nuclear weapon explosion. The outbreak is characterized by massive destruction of buildings, rubble, fires, and accidents in city utility networks. There are huge losses among the civilian population.

Types of damaging effects of radiation.

Radiation destroys body tissue.
The absorbed dose of radiation is an energy quantity measured in rads (1 rad = 0.01 J/kg) for all types of penetrating radiation. Different types of radiation have different effects on the human body. Therefore, the exposure dose of X-ray and gamma radiation is measured in roentgens (1P = 2.58 × 10–4 C/kg). The damage caused to human tissue by the absorption of radiation is assessed in units of equivalent radiation dose - rem (rem - the biological equivalent of x-rays). To calculate the dose in roentgens, it is necessary to multiply the dose in rads by the so-called. the relative biological effectiveness of the type of penetrating radiation under consideration. All people absorb some natural (background) penetrating radiation throughout their lives, and many absorb artificial radiation, such as X-rays. The human body appears to cope with this level of radiation. Harmful consequences are observed when either the total accumulated dose is too high or the exposure occurs in a short time. (However, the dose received as a result of uniform irradiation over a longer period of time can also lead to serious consequences.) As a rule, the received dose of radiation does not lead to immediate damage. Even lethal doses may have no effect for an hour or more. The expected results of human irradiation (whole body) with different doses of penetrating radiation are presented in table. 2. Table 2. Biological response of people to penetrating radiation

Rules of behavior and actions of the population in areas subject to radioactive contamination

It is obvious that from shelters, and even more so from anti-radiation or simple shelters that find themselves in a zone of dangerous (with a radiation level of more than 240 rad/h) radioactive contamination, the population will be evacuated to uncontaminated or slightly contaminated areas. This is due to the fact that long-term (several days) stay of people in protective structures is associated with serious physical and psychological stress. In this case, it will be necessary to quickly and carefully board the vehicle in order to be less exposed to radiation.

The presence of people in areas contaminated with radioactive substances outside shelters (shelters), despite the use of personal protective equipment, is associated with the possibility of dangerous exposure and, as a consequence, the development of radiation sickness. To prevent the severe consequences of radiation and reduce the manifestations of radiation sickness, in all cases of stay in a contaminated area it is necessary to carry out medical prevention of injuries from ionizing radiation.

Most of the available anti-radiation drugs are introduced into the body in such a way that they have time to penetrate into all cells and tissues before possible exposure to humans. The time for taking drugs is set depending on the method of their introduction into the body: drugs in tablets, for example, are taken 30-40 minutes, drugs are administered intramuscularly, 5 minutes before the start of possible radiation. It is recommended to use drugs in cases where a person has already been exposed to radiation. Anti-radiation drugs are produced in special kits intended for individual use.