Presentation on the topic "Atomic bomb"

Bystrov Kirill

Grade 11 MOU Sukromlenskaya secondary school, Torzhok district.

Tver region

Teacher: Mikhailov S.B.

Atomic bomb

A single-phase or single-stage explosive device in which the main energy output comes from the nuclear fission reaction of heavy nuclei (uranium-235 or plutonium) with the formation of lighter elements.

The atomic bomb is a nuclear weapon.

Classification of atomic bomb charges by power:

• up to 1 kt - ultra-small;
• 1 - 10 kt - small;
• 10 - 100 kt - medium;
• 100-1000 ct - large;
• over 1 Mt - super-large.

Atomic bomb device

An atomic bomb includes a number of different components. As a rule, two main elements of this type of weapon are distinguished: the body and the automation system.

The case contains a nuclear charge and automation, and it is he who performs a protective function in relation to various types effects (mechanical, thermal, etc.). And the role of the automation system is to ensure that the explosion occurs at a clearly defined time, and not earlier or later. The automation system consists of such systems as: emergency detonation; protection and cocking; power supply; detonation and detonation sensors.

The history of the creation of the atomic bomb

The history of the creation of the atomic bomb, and in particular weapons, begins in 1939, with the discovery made by Joliot-Curie. It was from that moment that scientists realized that a uranium chain reaction could become not only a source of enormous energy, but also a terrible weapon. And so, the device of the atomic bomb is based on the use of nuclear energy, which is released during a nuclear chain reaction.

The latter implies the process of fission of heavy nuclei or the synthesis of light nuclei. As a result, the atomic bomb is a weapon mass destruction, due to the fact that in the shortest period of time there is a release huge amount intranuclear energy in a small space.

First atomic bomb test

The first test of an atomic weapon was carried out by the US military on July 16, 1945, at a place called Almogordo, which showed the full power of atomic energy. After that, the atomic bombs available to the US forces were loaded onto a warship and sent to the shores of Japan. The refusal of the Japanese government from a peaceful dialogue made it possible to demonstrate in action the full power of atomic weapons, the victims of which were the city of Hiroshima first, and a little later Nagasaki.

And just four days later, military base The United States immediately left two aircraft with dangerous goods on board, the targets of which were Kokura and Nagasaki. From the atomic bomb in Nagasaki in the first days, 73 thousand people died. the list has already been added to 35 thousand people.

• shock wave ( the speed of propagation of a shock wave in a medium exceeds the speed of sound in this medium)
• light emission ( power is many times greater than the power of the sun's rays)
• penetrating radiation
• radioactive contamination
• electromagnetic pulse (EMP) (disables equipment and devices)
• x-rays

shock wave

Main striking

factor of a nuclear explosion.

Represents

region of sharp compression

environment, spreading

in all directions from the place

supersonic explosion

speed.

light emission

A stream of radiant energy, including visible,

ultraviolet and

infrared rays.

Spreads almost

instantly and lasts

dependencies

from nuclear power

explosion up to 20s.

electromagnetic pulse

A short-term electromagnetic field that occurs during the explosion of a nuclear weapon as a result of the interaction of gamma rays and neutrons emitted during a nuclear explosion with the atoms of the environment.

The action of the atomic bomb

After the explosion, a bright flash will occur, turning into a fiery sphere, which, as it cools, turns into a nuclear mushroom cap. Next comes light emission. The pressure of the shock wave at the boundary of the fire sphere with its maximum development is 7 atmospheres (0.7 MPa), regardless of power, the air temperature in the wave is about 350 degrees, and in combination with light radiation, objects at the boundary of the sphere can heat up to 1200 degrees during an explosion with power in 1 megaton.

In the case of a person, heat will spread throughout the body. The light makes clothes even tighter, welding them to the body. The duration of the flash depends on the power of the explosion, from about one second at one kiloton to forty seconds at fifty megatons; one megaton will shine for ten seconds, twenty kilotons (Hiroshima) for three seconds. The shock wave can go before the end of the glow.

• Soviet intelligence had information about work on the creation of the atomic bomb in the United States coming from atomic physicists who sympathize with the USSR, in particular Klaus Fuchs. This information was reported Beria Stalin. However, it is believed that the letter of the Soviet physicist addressed to him in early 1943 was of decisive importance. Flerova who managed to explain the essence of the problem popularly. As a result 11 February 1943 a resolution was adopted GKO about the beginning of work on the creation of an atomic bomb. General leadership was entrusted to the Deputy Chairman of the State Defense Committee V. M. Molotova, who, in turn, appointed the head of the atomic project I. Kurchatova(his appointment was signed 10th of March). The information received through intelligence channels facilitated and accelerated the work of Soviet scientists.

• On November 6, 1947, the Minister of Foreign Affairs of the USSR, V. M. Molotov, made a statement regarding the secret of the atomic bomb, saying that "this secret has long ceased to exist." This statement meant that Soviet Union has already discovered the secret of atomic weapons, and he has these weapons at his disposal. The scientific circles of the United States of America accepted this statement by V. M. Molotov as a bluff, believing that the Russians could master atomic weapons no earlier than 1952.

• U.S. spy satellites have located the exact location of Russian tactical nuclear weapons in the Kaliningrad region, contradicting Moscow's claims that tactical weapons have been transferred there.

• The successful test of the first Soviet atomic bomb was carried out on August 29, 1949 at the built test site in Semipalatinsk regions of Kazakhstan. On September 25, 1949, the newspaper " Is it true» posted a message TASS"in connection with the statement of US President Truman on the conduct of an atomic explosion in the USSR":

"Nuclear Club"

An informal name for a group of countries with nuclear weapons. It includes the USA (since 1945), Russia (originally the Soviet Union: since 1949), Great Britain (1952), France (1960), China (1964), India (1974), Pakistan (1998) and North Korea (2006). Israel is also considered to have nuclear weapons.

The "old" nuclear powers of the USA, Russia, Great Britain, France and China are the so-called. the nuclear five - that is, the states that are considered "legitimate" nuclear powers under the Treaty on the Non-Proliferation of Nuclear Weapons. The remaining countries with nuclear weapons are called "young" nuclear powers.

In addition, several states that are members of NATO and other allies have or may have US nuclear weapons on their territory. Some experts believe that in certain circumstances, these countries can take advantage of it.

Introduction In the history of mankind, individual events become epoch-making. The creation of atomic weapons and their use was caused by the desire to rise to a new level in mastering the perfect method of destruction. Like any event, the creation of atomic weapons has its own history...

The history of the creation of nuclear weapons. At the very end of the 20th century, Antoine Henri Becquerel discovered the phenomenon of radioactivity The discovery of the atomic nucleus by Rutherford and E. Rutherford. Since the beginning of 1939, a new phenomenon has been studied immediately in England, France, the USA and the USSR. E.Rutherford

Finishing spurt In 1939, the Second World War. In October 1939, the first government committee on atomic energy appears in the USA. In Germany In 1942, failures on the German-Soviet front led to a reduction in work on nuclear weapons. The United States began to lead in the creation of weapons.

Tests of atomic weapons. On the morning of August 6, 1945, there was a clear, cloudless sky over Hiroshima. As before, the approach of two American planes from the east caused no alarm. One of the planes dived and threw something, then both planes flew back.

Nuclear Priority A parachute dropped object slowly descended and suddenly exploded at a height of 600m above the ground. The city was destroyed with one blow: out of 90 thousand buildings, 65 thousand were destroyed. Out of 250 thousand inhabitants, 160 thousand were killed and wounded.

Nagasaki was scheduled for August 11 new attack. On the morning of August 8, the weather service reported that target 2 (Kokura) on August 11 would be covered by clouds. And so the second bomb was dropped on Nagasaki. This time, about 73 thousand people died, another 35 thousand died after much torment.

Nuclear weapon in USSR. On November 3, 1945, the Pentagon received a 329 report on the selection of the 20 most important targets in the USSR. In the United States, a plan for war was ripe. The start of hostilities was scheduled for January 1, 1950. The Soviet nuclear project lagged behind the American one by exactly four years. In December 1946, I. Kurchatov launched the first nuclear reactor in Europe. But be that as it may, the USSR had an atomic bomb, and on October 4, 1957, the USSR launched the first artificial Earth satellite into space. Thus, the beginning of the Third World War was prevented! I. Kurchatov

Conclusion. Hiroshima and Nagasaki are a warning for the future! According to experts, our planet is dangerously oversaturated with nuclear weapons. Such arsenals are fraught with a huge danger for the entire planet, and not for individual countries. Their creation absorbs huge material resources that could be used to fight diseases, illiteracy, poverty in a number of other regions of the world.

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Weapons of Mass Destruction Types of weapons that, as a result of their use, can lead to mass destruction or destruction of enemy manpower and equipment, are commonly called weapons of mass destruction.

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On August 6, 1945, at 8:11 am, a fireball hit the city. In an instant, he burned alive and maimed hundreds of thousands of people. Thousands of houses turned into ashes, which were thrown up by a stream of air for several kilometers. The city flared up like a torch... Deadly particles began their destructive work within a radius of one and a half kilometers. The US Air Command only learned on August 8 of the actual extent of the destruction of Hiroshima. The results of aerial photography showed that on an area of ​​about 12 sq. km. 60 percent of the buildings were turned to dust, the rest were destroyed. The city ceased to exist. As a result of the atomic bombing, more than 240 thousand inhabitants of Hiroshima died (at the time of the bombing, the population was about 400 thousand people.

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The history of the creation of atomic weapons Shortly after the demonstration of force in August 1945, America begins to develop the use of nuclear weapons against other states of the world, primarily the USSR. So a plan was developed, called "Totality", using 20-30 atomic bombs. In June 1946, the development of a new plan was completed, which received the code name "Pincers". According to it, an atomic strike was envisaged against the USSR with the use of 50 atomic bombs. 1948 In the new plan "Sizl" ("Sizzling Heat"), in particular, nuclear strikes were planned on Moscow with eight bombs and on Leningrad with seven. In total, it was planned to drop 133 atomic bombs on 70 Soviet cities. In the fall of 1949, the Soviet Union tested its atomic bomb. By the beginning of 1950, a new American plan for waging war against the USSR was developed, which received the code name "Dropshot" ("Instant Strike"). Only at its first stage it was supposed to drop 300 atomic bombs on 200 cities of the Soviet Union. At the training ground in Alamogordo on July 16, 1945.

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The history of the creation of atomic weapons In August 1953, a nuclear explosion of a bomb with a power of 300-400kt was carried out in the USSR. From that moment on, we can talk about the beginning of an arms race. The United States built up strategic armaments at the expense of bombers. The Soviet Union considered missiles a priority means of delivering nuclear weapons. After World War 2, they worked on the creation of an analogue of the German rocket A-4 (V-2), apparently, two groups, one was recruited from German specialists who were unable to escape to the west, the other was Soviet, under the leadership of S.P. Queen. Both missiles were tested in October 1947. The R-1 missile, developed by the Soviet group, turned out to be better than the 300 km range missile developed by the German group, and was put into service.

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Creation of the Soviet nuclear arsenal: key events December 25, 1946 1947 August 19, 1949 August 12, 1953 End of 1953 1955 1955 September 21, 1955 August 3, 1957 October 11, 1961 October 30, 1961 1962 1984 1985 The first controlled nuclear reaction in the USSR was carried out The first one was tested soviet rocket- German version The first nuclear device in the USSR was blown up The first thermonuclear device in the USSR was blown up The first nuclear weapon was transferred to the Armed Forces The first heavy bomber was adopted The IRBM (medium-range ballistic missile) was adopted The first underwater nuclear explosion rocket) First Soviet underground nuclear explosion A 58 Mt device, the most powerful device ever detonated, the first Soviet Tu-22 supersonic bomber was adopted The first long-range cruise missile of a new generation The first Soviet mobile ICBM was deployed

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NUCLEAR WEAPONS (obsolete - atomic weapon) - a weapon of mass destruction of explosive action, based on the use of intranuclear energy, which is released during chain reactions of fission of heavy nuclei of some isotopes of uranium and plutonium or during thermonuclear fusion reactions of light hydrogen isotope nuclei - deuterium and tritium into heavier ones, for example nuclei of helium isotopes. Nuclear weapons include various nuclear munitions (warheads of missiles and torpedoes, aviation and depth charges, artillery shells and land mines filled with nuclear charges), their means of delivering them to the target, and means of control.

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Nuclear weapons Damaging factors High-altitude Air Ground (surface) Underground (underwater) Shock wave Light radiation Penetrating radiation Radioactive contamination Electromagnetic pulse

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A ground (surface) nuclear explosion is an explosion produced on the surface of the earth (water), in which the luminous area touches the surface of the earth (water), and the dust (water) column from the moment of formation is connected to the explosion cloud.

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An underground (underwater) nuclear explosion is an explosion produced underground (under water) and characterized by the release of a large number soil (water) mixed with nuclear products explosive(fragments of fission of uranium-235 or plutonium-239).

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A high-altitude nuclear explosion is an explosion made to destroy missiles and aircraft in flight at an altitude safe for ground objects (over 10 km).

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An air nuclear explosion is an explosion produced at an altitude of up to 10 km, when the luminous area does not touch the ground (water).

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It is a stream of radiant energy, including ultraviolet, visible and infrared radiation. The source of light radiation is a luminous area consisting of hot explosion products and hot air. The brightness of light radiation in the first second is several times greater than the brightness of the Sun. The absorbed energy of light radiation is converted into heat, which leads to heating of the surface layer of the material and can lead to huge fires. Light radiation from a nuclear explosion

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Injury, protection Light radiation can cause skin burns, eye damage and temporary blindness. Burns occur from direct exposure to light radiation on open areas of the skin (primary burns), as well as from burning clothes, in fires (secondary burns). Temporary blindness usually occurs at night and at dusk and does not depend on the direction of gaze at the time of the explosion and will be widespread. During the day, it arises only when looking at the explosion. Temporary blindness passes quickly, leaves no consequences, and medical attention is usually not required. Protection from light radiation can be any barriers that do not let light through: shelters, the shadow of a thick tree, a fence, etc.

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The shock wave of a nuclear explosion It is a region of sharp air compression, which propagates from the center of the explosion at supersonic speed. Its action lasts for several seconds. A shock wave travels a distance of 1 km in 2 s, 2 km in 5 s, and 3 km in 8 s. The front boundary of the compressed air layer is called the front of the shock wave.

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Injuries to people, protection Injuries to people are divided into: Extremely severe - fatal injuries (at an overpressure of 1 kg / cm2); Severe (pressure 0.5 kg / cm2) - characterized by a strong contusion of the whole organism; in this case, damage to the brain and abdominal organs can be observed, heavy bleeding from the nose and ears, severe fractures and dislocations of the limbs. Medium - (pressure 0.4 - 0.5 kg / cm2) - a serious contusion of the whole body, damage to the hearing organs. Bleeding from the nose, ears, fractures, severe dislocations, lacerations Lungs - (pressure 0.2-0.4 kg / cm2) are characterized by temporary damage to the hearing organs, general mild contusion, bruises and dislocations of the limbs. Protection of the population from the shock wave reliably protects shelters and shelters in basements and other solid structures, recesses in the area.

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Penetrating radiation It is a combination of gamma radiation and neutron radiation. Gamma quanta and neutrons, propagating in any medium, cause its ionization. Under the action of neutrons, in addition, non-radioactive atoms of the medium are converted into radioactive ones, i.e., the so-called induced activity is formed. As a result of the ionization of atoms that make up a living organism, the vital processes of cells and organs are disrupted, which leads to radiation sickness. Protection of the population - only shelters, anti-radiation shelters, reliable basements and cellars.

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Radioactive contamination of the area Occurs as a result of the fallout of radioactive substances from the cloud of a nuclear explosion during its movement. Gradually settling on the surface of the earth, radioactive substances create a site of radioactive contamination, which is called a radioactive trace. Zone of moderate infection. Within this zone, during the first day, unprotected people can receive a radiation dose higher than the permissible norms (35 rad). Protection - ordinary houses. Zone of severe infection. The danger of infection persists up to three days after the formation of a radioactive trace. Protection - shelters, PRU. The zone of extremely dangerous infection. The defeat of people can occur even when they are in the PRU. Evacuation required.

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Electromagnetic pulse This is a short-wave electromagnetic field that occurs when a nuclear weapon explodes. About 1% of the total energy of the explosion is spent on its formation. The duration of the action is several tens of milliseconds. The impact of e.i. can lead to the combustion of sensitive electronic and electrical components with large antennas, damage to semiconductor, vacuum devices, capacitors. People can only be hit at the moment of explosion when they come into contact with extended wire lines.

"The phenomenon of radioactivity" - In 1901 he discovered the physiological effect of radioactive radiation. At home: §48, no.233. When a neutron decays, it becomes a proton and an electron. In 1903, Becquerel was awarded Nobel Prize for the discovery of the natural radioactivity of uranium. ?-particle - the nucleus of a helium atom. Scheme? - decay. The main works are devoted to radioactivity and optics.

"Lesson Radioactivity" - 2. The half-life of a radioactive substance is 1 hour. 13. Biological effect of radiation. For radioactive atoms (more precisely, nuclei) there is no concept of age. 5. How many protons and neutrons does the following chemical element? The purpose of the lesson: The period of radioactive decay and differential equations.

"Nuclear weapons" - Types of explosions. Weapons of mass destruction. Nuclear weapon. Zone of moderate infection. electromagnetic impulse. Defeat people, protection. Radioactive contamination of the area. Protection - shelters, PRU. Ground (Surface). The duration of the action is several tens of milliseconds. Air. In total, it was planned to drop 133 atomic bombs on 70 Soviet cities.

"Physics Radioactivity" - Radioactivity in physics. Positively charged particles are called alpha particles, negatively charged particles are called beta particles, and neutral particles are called gamma particles (?-particles,?-particles,?-particles). Polonium. Radioactivity (from the Latin radio - I radiate, radus - a beam and activus - effective), this name was given to an open phenomenon, which turned out to be the privilege of the heaviest elements of the periodic system of D.I. Mendeleev.

"The use of isotopes" - The mechanism of nuclear fission of the uranium atom Characteristics of radioactive radiation About radiation. The use of isotopes in diagnostics Therapeutic use isotopes. Therapeutic use of radium Determining the age of the Earth. Application of natural radioactive elements. The use of artificial radioactive elements.

"The law of radioactive decay" - P. Vilard. Properties of radioactive radiation. Displacement rules. THE LAW OF RADIOACTIVE DECAY MOU "Secondary School No. 56", Novokuznetsk Sergeeva TV, teacher of physics. radioactive decays. In 1896, Henri Becquerel discovered the phenomenon of radioactivity. E. Rutherford. The nature of alpha, beta, gamma radiation. The half-life is the main quantity that determines the rate of radioactive decay.

In total there are 14 presentations in the topic

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Foreword The creation of the Soviet atomic bomb (the military part of the USSR atomic project) - the history of fundamental research, the development of technologies and their practical implementation in the USSR, aimed at creating weapons of mass destruction using nuclear energy. The events were stimulated to a large extent by the activities in this direction of scientific institutions and the military industry of Western countries, including Nazi Germany, and later the United States.

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The background of the Soviet project It included: Works until 1941 The role of the activities of the Radium Institute Work in 1941-1943: a) Foreign intelligence information b) Launch of the atomic project

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Work until 1941 In 1930-1941, work was actively carried out in the nuclear field. In this decade, fundamental radiochemical research was also carried out. Since the beginning of the 1920s, work has been intensively developed at the Radium Institute and at the first Fiztekh. Academician V. G. Khlopin was considered an authority in this area. Also a serious contribution was made by the employees of the Radium Institute: G. A. Gamov, I. V. Kurchatov and L. V. Mysovsky. The Soviet project was supervised by the Chairman of the Council of People's Commissars of the USSR V. M. Molotov. In 1941, with the beginning of the Great Patriotic War nuclear studies were classified

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The Role of the Radium Institute The chronology of research carried out by the employees of the Radium Institute in Leningrad shows that work in this direction has not been completely curtailed. Back in 1938, the first laboratory of artificial radioactive elements in the USSR was created here. Under the chairmanship of V. G. Khlopin, the Uranium Commission of the USSR Academy of Sciences was formed, in 1942, during the evacuation of the institute, A. P. Zhdanov and L. V. Mysovsky opened the new kind nuclear fission - the complete collapse of the atomic nucleus under the action of multiply charged particles of cosmic rays. The Radium Institute was entrusted with the development of a technology for separating eka-rhenium (Z = 93) and eka-osmium (Z = 94) from neutron-irradiated uranium. By 1949, the amount of plutonium necessary for testing nuclear weapons had been produced.

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Work in 1941-1943 Foreign intelligence information: Already in September 1941, intelligence information began to arrive in the USSR about the conduct of secret intensive research work in the UK and the USA aimed at developing methods for using atomic energy for military purposes and creating atomic bombs of huge destructive strength. In May 1942, the leadership of the GRU informed the USSR Academy of Sciences of the presence of reports of work abroad on the problem of using atomic energy for military purposes. Soviet intelligence had detailed information about the work on the creation of an atomic bomb in the United States, which came from specialists who understood the danger of a nuclear monopoly or sympathized with the USSR

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Work in 1941-1943 Launch of the atomic project: On September 28, 1942, a month and a half after the launch of the Manhattan Project, GKO Resolution No. 2352ss "On the organization of work on uranium" was adopted. The order provided for the organization for this purpose at the USSR Academy of Sciences of a special laboratory of the atomic nucleus, the creation of laboratory facilities for the separation of uranium isotopes and the conduct of a complex of experimental work.

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Work on the creation of an atomic bomb On February 11, 1943, GKO resolution No. 2872ss was adopted on the start of practical work on the creation of an atomic bomb. On April 12, 1943, Academician A. A. Baikov, vice-president of the USSR Academy of Sciences, signed an order on the creation of Laboratory No. 2 of the USSR Academy of Sciences. I.V. was appointed Head of the Laboratory. Kurchatov. GKO Decree No. 5582ss of April 8, 1944 ordered the People's Commissariat of the Chemical Industry to design in 1944 a workshop for the production of heavy water and a plant for the production of uranium hexafluoride, and the People's Commissariat of Nonferrous Metallurgy to ensure in 1944 the production of 500 kg of metal at a pilot plant uranium and build by January 1, 1945 a workshop for the production of metallic uranium and supply Laboratory No. 2 in 1944 with tens of tons of high-quality graphite blocks. I.V. A. A. KURCHATOV BAIKOV

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post-war period On August 20, 1945, to manage the atomic project, the GKO created a Special Committee with emergency powers, headed by L.P. Beria. Under the Special Committee was created executive agency- The first main department under the Council of People's Commissars of the USSR (PGU). Also during 1945, hundreds of German scientists who were related to the nuclear problem were brought from Germany to the USSR on a voluntary-compulsory basis. This greatly accelerated the creation of the bomb. L.P. BERIA

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The first Soviet atomic bomb RDS-1 (the so-called "product 501") was created in the former KB-11 under the scientific supervision of Igor Vasilievich Kurchatov and Yuli Borisovich Khariton. It was structurally reminiscent of the American bomb "Fat Man". The design of the RDS-1 bomb was a plutonium aviation atomic bomb of a characteristic "drop-shaped" shape with a mass of 4.7 tons, a diameter of 1.5 m and a length of 3.3 m. The explosion occurred at exactly the scheduled time, subsequently, its power was estimated at 22 kilotons.The US nuclear monopoly has sunk into oblivion, the Soviet Union won the right to exist.

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Tests Successful testing of the first Soviet atomic bomb was carried out on August 29, 1949 at the constructed test site in the Semipalatinsk region of Kazakhstan. It was kept secret. On September 3, 1949, an aircraft of the US Special Meteorological Intelligence Service took air samples in the Kamchatka region, and then American specialists found isotopes in them, which indicated that a nuclear explosion had been carried out in the USSR. The explosion of the first Soviet nuclear device at the Semipalatinsk test site on August 29, 1949. 10 hours 05 minutes.