Scientists who created nuclear weapons. Creation of the atomic bomb in the USSR

In the USA and the USSR, work began simultaneously on atomic bomb projects. In 1942, in August, the secret Laboratory No. 2 began to operate in one of the buildings located in the courtyard of Kazan University. Igor Kurchatov, the Russian "father" of the atomic bomb, became the head of this facility. At the same time in August, not far from Santa Fe, New Mexico, in the building of the former local school, the Metallurgical Laboratory, also secret, began to operate. It was led by Robert Oppenheimer, the "father" of the atomic bomb from America.

It took a total of three years to complete the task. The first US was blown up at the test site in July 1945. Two more were dropped on Hiroshima and Nagasaki in August. It took seven years for the birth of the atomic bomb in the USSR. The first explosion took place in 1949.

Igor Kurchatov: short biography

The "father" of the atomic bomb in the USSR was born in 1903, on January 12. This event took place in the Ufa province, in today's city of Sim. Kurchatov is considered one of the founders of peaceful purposes.

He graduated with honors from the Simferopol Men's Gymnasium, as well as a craft school. Kurchatov in 1920 entered the Tauride University, the department of physics and mathematics. After 3 years, he successfully graduated from this university ahead of schedule. The "father" of the atomic bomb in 1930 began working at the Physico-Technical Institute of Leningrad, where he headed the physics department.

The era before Kurchatov

Back in the 1930s, work related to atomic energy began in the USSR. Chemists and physicists from various scientific centers, as well as specialists from other states, took part in all-Union conferences organized by the USSR Academy of Sciences.

Radium samples were obtained in 1932. And in 1939 the chain reaction of fission of heavy atoms was calculated. The year 1940 became a landmark in the nuclear field: the design of the atomic bomb was created, and methods for the production of uranium-235 were also proposed. Conventional explosives were first proposed to be used as a fuse to initiate a chain reaction. Also in 1940, Kurchatov presented his report on the fission of heavy nuclei.

Research during the Great Patriotic War

After the Germans attacked the USSR in 1941, nuclear research was suspended. The main Leningrad and Moscow institutes that dealt with the problems of nuclear physics were urgently evacuated.

The head of strategic intelligence, Beria, knew that Western physicists considered atomic weapons an achievable reality. According to historical data, back in 1939, Robert Oppenheimer, the leader of the work on the creation of the atomic bomb in America, came to the USSR incognito in September. The Soviet leadership could have learned about the possibility of obtaining these weapons from the information provided by this "father" of the atomic bomb.

In 1941, intelligence data from the UK and the USA began to arrive in the USSR. According to this information, intensive work has been launched in the West, the purpose of which is the creation of nuclear weapons.

In the spring of 1943, Laboratory No. 2 was established to produce the first atomic bomb in the USSR. The question arose as to whom to entrust the leadership of it. The list of candidates initially included about 50 names. Beria, however, stopped his choice on Kurchatov. He was called in October 1943 to the bride in Moscow. Today, the scientific center that grew out of this laboratory bears his name - "Kurchatov Institute".

In 1946, on April 9, a decree was issued on the creation of a design bureau at Laboratory No. 2. It was only at the beginning of 1947 that the first production buildings were ready, which were located in the zone of the Mordovian Reserve. Some of the laboratories were located in monastic buildings.

RDS-1, the first Russian atomic bomb

They called the Soviet prototype RDS-1, which, according to one version, meant special. "After some time, this abbreviation began to be deciphered a little differently -" Stalin's Jet Engine ". In documents to ensure secrecy, the Soviet bomb was called "rocket engine."

It was a device whose power was 22 kilotons. The development of atomic weapons was carried out in the USSR, but the need to catch up with the United States, which had gone ahead during the war, forced domestic science to use data obtained by intelligence. The basis of the first Russian atomic bomb was taken "Fat Man", developed by the Americans (pictured below).

It was on August 9, 1945 that the United States dropped it on Nagasaki. "Fat Man" worked on the decay of plutonium-239. The detonation scheme was implosive: the charges exploded along the perimeter of the fissile material and created an explosive wave that "compressed" the substance located in the center and caused a chain reaction. This scheme was subsequently recognized as ineffective.

The Soviet RDS-1 was made in the form of a large diameter and mass of a free-falling bomb. Plutonium was used to make an explosive atomic device. Electrical equipment, as well as the RDS-1 ballistic body, were domestically developed. The bomb consisted of a ballistic body, a nuclear charge, an explosive device, as well as equipment for automatic charge detonation systems.

Uranium deficiency

Soviet physics, taking the plutonium bomb of the Americans as a basis, faced a problem that had to be solved in the shortest possible time: the production of plutonium at the time of development had not yet begun in the USSR. Therefore, captured uranium was originally used. However, the reactor required at least 150 tons of this substance. In 1945, mines in East Germany and Czechoslovakia resumed their work. Uranium deposits in the Chita region, Kolyma, Kazakhstan, Central Asia, the North Caucasus and Ukraine were found in 1946.

In the Urals, near the city of Kyshtym (not far from Chelyabinsk), they began to build "Mayak" - a radiochemical plant, and the first industrial reactor in the USSR. Kurchatov personally supervised the laying of uranium. Construction was launched in 1947 in three more places: two in the Middle Urals and one in the Gorky region.

Construction work proceeded at a fast pace, but uranium was still not enough. The first industrial reactor could not be launched even by 1948. Only on June 7 of this year was the uranium loaded.

Nuclear reactor start-up experiment

The "father" of the Soviet atomic bomb personally took over the duties of the chief operator at the nuclear reactor control panel. On June 7, between 11 and 12 am, Kurchatov began an experiment to launch it. The reactor on June 8 reached a capacity of 100 kilowatts. After that, the "father" of the Soviet atomic bomb drowned out the chain reaction that had begun. The next stage of preparation of the nuclear reactor continued for two days. After the cooling water was supplied, it became clear that the uranium available was not enough to carry out the experiment. The reactor reached a critical state only after loading the fifth portion of the substance. The chain reaction has become possible again. It happened at 8 am on June 10.

On the 17th of the same month, Kurchatov, the creator of the atomic bomb in the USSR, made an entry in the journal of shift supervisors in which he warned that the water supply should not be stopped in any case, otherwise an explosion would occur. On June 19, 1938, at 12:45, an industrial start-up of a nuclear reactor, the first in Eurasia, took place.

Successful bomb tests

In 1949, in June, 10 kg of plutonium was accumulated in the USSR - the amount that was put into the bomb by the Americans. Kurchatov, the creator of the atomic bomb in the USSR, following the decree of Beria, ordered the test of the RDS-1 to be scheduled for August 29.

A section of the Irtysh waterless steppe, located in Kazakhstan, not far from Semipalatinsk, was set aside for a test site. In the center of this experimental field, whose diameter was about 20 km, a metal tower 37.5 meters high was constructed. RDS-1 was installed on it.

The charge used in the bomb was a multi-layered design. In it, the transition to the critical state of the active substance was carried out by compressing it using a spherical converging detonation wave, which was formed in the explosive.

Consequences of the explosion

The tower was completely destroyed after the explosion. A crater appeared in its place. However, the main damage was caused by the shock wave. According to the description of eyewitnesses, when a trip to the explosion site took place on August 30, the experimental field was a terrible picture. Highway and railway bridges were thrown back to a distance of 20-30 m and mangled. Cars and wagons were scattered at a distance of 50-80 m from the place where they were located, residential buildings were completely destroyed. The tanks used to test the strength of the blow lay on their sides with their turrets knocked down, and the guns were a pile of mangled metal. Also, 10 Pobeda vehicles, specially brought here for the experiment, burned down.

In total, 5 RDS-1 bombs were made. They were not transferred to the Air Force, but were stored in Arzamas-16. Today in Sarov, which was formerly Arzamas-16 (the laboratory is shown in the photo below), a mock-up bomb is on display. It is in the local nuclear weapons museum.

"Fathers" of the atomic bomb

Only 12 Nobel laureates, future and present, participated in the creation of the American atomic bomb. In addition, they were assisted by a group of scientists from Great Britain, which was sent to Los Alamos in 1943.

In Soviet times, it was believed that the USSR solved the atomic problem completely independently. Everywhere it was said that Kurchatov, the creator of the atomic bomb in the USSR, was her "father". Although rumors of secrets stolen from the Americans occasionally leaked out. And only in the 1990s, 50 years later, Yuli Khariton - one of the main participants in the events of that time - spoke about the great role of intelligence in the creation of the Soviet project. The technical and scientific results of the Americans were mined by Klaus Fuchs, who arrived in the English group.

Therefore, Oppenheimer can be considered the "father" of bombs that were created on both sides of the ocean. We can say that he was the creator of the first atomic bomb in the USSR. Both projects, American and Russian, were based on his ideas. It is wrong to consider Kurchatov and Oppenheimer only outstanding organizers. We have already talked about the Soviet scientist, as well as about the contribution made by the creator of the first atomic bomb to the USSR. Oppenheimer's main achievements were scientific. It was thanks to them that he turned out to be the head of the atomic project, just like the creator of the atomic bomb in the USSR.

Short biography of Robert Oppenheimer

This scientist was born in 1904, April 22, in New York. in 1925 he graduated from Harvard University. The future creator of the first atomic bomb was trained for a year at the Cavendish Laboratory at Rutherford. A year later, the scientist moved to the University of Göttingen. Here, under the guidance of M. Born, he defended his doctoral dissertation. In 1928 the scientist returned to the USA. The "father" of the American atomic bomb from 1929 to 1947 taught at two universities in this country - the California Institute of Technology and the University of California.

On July 16, 1945, the first bomb was successfully tested in the United States, and soon after that, Oppenheimer, along with other members of the Provisional Committee created under President Truman, was forced to choose targets for future atomic bombing. Many of his colleagues by that time were actively opposed to the use of dangerous nuclear weapons, which was not necessary, since the surrender of Japan was a foregone conclusion. Oppenheimer did not join them.

Explaining his behavior later, he said that he relied on politicians and the military, who were better acquainted with the real situation. In October 1945, Oppenheimer ceased to be director of the Los Alamos Laboratory. He began work in Preston, heading the local research institute. His fame in the United States, as well as outside this country, reached its climax. New York newspapers wrote about him more and more often. President Truman presented Oppenheimer with the Medal of Merit, which was the highest decoration in America.

He wrote, in addition to scientific works, several "Open Mind", "Science and Everyday Knowledge" and others.

This scientist died in 1967, on February 18. Oppenheimer has been a heavy smoker since his youth. In 1965 he was diagnosed with cancer of the larynx. At the end of 1966, after an operation that did not bring results, he underwent chemotherapy and radiotherapy. However, the treatment had no effect, and on February 18 the scientist died.

So, Kurchatov is the "father" of the atomic bomb in the USSR, Oppenheimer - in the USA. Now you know the names of those who were the first to work on the development of nuclear weapons. Having answered the question: "Who is called the father of the atomic bomb?", we told only about the initial stages of the history of this dangerous weapon. It continues to this day. Moreover, new developments are being actively carried out in this area today. The "father" of the atomic bomb - the American Robert Oppenheimer, as well as the Russian scientist Igor Kurchatov were only pioneers in this matter.

Creation of the Soviet atomic bomb(military part of the atomic project of the USSR) - fundamental research, 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 other countries, primarily Nazi Germany and the United States [ ] . On August 9, 1945, American planes dropped two atomic bombs on the Japanese cities of Hiroshima and Nagasaki. Almost half of the civilians died immediately in the explosions, others were seriously ill and continue to die to this day.

Encyclopedic YouTube

1 / 5
In 1930-1941, work was actively carried out in the nuclear field.
In this decade, fundamental radiochemical research was carried out, without which a complete understanding of these problems, their development, and, moreover, their implementation is generally unthinkable.

Work in 1941-1943

Foreign intelligence information

As early as September 1941, the USSR began to receive intelligence information 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 enormous destructive power. One of the most important documents received back in 1941 by Soviet intelligence is the report of the British “MAUD Committee”. From the materials of this report, received through the channels of the foreign intelligence NKVD USSR from Donald MacLean, it followed that the creation of an atomic bomb was real, that it could probably be created even before the end of the war and, therefore, could affect its course.
Intelligence information about work on the problem of atomic energy abroad, which was available in the USSR at the time of the decision to resume work on uranium, was received both through the channels of the NKVD intelligence and through the channels of the Main Intelligence Directorate of the General Staff (GRU) of the Red Army.
In May 1942, the leadership of the GRU informed the Academy of Sciences of the USSR about the presence of reports of work abroad on the problem of using atomic energy for military purposes and asked to be informed whether this problem currently has a real practical basis. In June 1942, the answer to this request was given by V. G. Khlopin, who noted that over the past year, almost no works related to the solution of the problem of using atomic energy have been published in the scientific literature.
An official letter from the head of the NKVD L.P. Beria addressed to I.V. Stalin with information about the work on the use of atomic energy for military purposes abroad, proposals for organizing these works in the USSR and secret acquaintance with the materials of the NKVD of prominent Soviet specialists, the variants of which were prepared by the NKVD officers back in late 1941 - early 1942, it was sent to I.V. Stalin only in October 1942, after the adoption of the GKO order to resume work on uranium in the USSR.
Soviet intelligence had detailed information about the work on the creation of an atomic bomb in the United States, coming from specialists who understood the danger of a nuclear monopoly or sympathizers of the USSR, in particular, Klaus Fuchs, Theodor Hall, Georges Koval and David Greenglass. However, according to some, a letter addressed to Stalin in early 1943 by the Soviet physicist G. Flerov, who managed to explain the essence of the problem in a popular way, was of decisive importance. On the other hand, there is reason to believe that G. N. Flerov's work on the letter to Stalin was not completed and it was not sent.
The hunt for the data of America's uranium project began at the initiative of Leonid Kvasnikov, head of the scientific and technical intelligence department of the NKVD, back in 1942, but fully unfolded only after the arrival in Washington of the famous couple of Soviet intelligence officers: Vasily Zarubin and his wife Elizaveta. It was with them that the NKVD resident in San Francisco, Grigory Kheifits, interacted, saying that the most prominent American physicist Robert Oppenheimer and many of his colleagues left California for an unknown place where they would be creating some kind of superweapon.
To double-check the data of "Charon" (this was the code name of Heifitz) was entrusted to Lieutenant Colonel Semyon Semenov (pseudonym "Twain"), who had worked in the United States since 1938 and had assembled a large and active intelligence group there. It was Twain who confirmed the reality of the work on the creation of the atomic bomb, named the code for the Manhattan Project and the location of its main scientific center - the former colony for juvenile delinquents Los Alamos in New Mexico. Semyonov also gave the names of some scientists who worked there, who at one time were invited to the USSR to participate in large Stalinist construction projects and who, having returned to the USA, did not lose ties with the extreme left organizations.

Thus, Soviet agents were introduced into the scientific and design centers of America, where a nuclear weapon was created. However, in the midst of establishing intelligence operations, Lisa and Vasily Zarubin were urgently recalled to Moscow. They were lost in conjecture, because not a single failure happened. It turned out that the Center received a denunciation from Mironov, an employee of the residency, who accused the Zarubins of treason. And for almost half a year, Moscow counterintelligence checked these accusations. They were not confirmed, however, the Zarubins were no longer allowed to go abroad.
In the meantime, the work of the embedded agents had already brought the first results - reports began to arrive, and they had to be immediately sent to Moscow. This work was entrusted to a group of special couriers. The most operative and fearless were the Coens, Maurice and Lona. After Maurice was drafted into the US Army, Lona began to independently deliver information materials from New Mexico to New York. To do this, she traveled to the small town of Albuquerque, where, for appearances, she visited a tuberculosis dispensary. There she met with agents undercover nicknames "Mlad" and "Ernst".
However, the NKVD still managed to extract several tons of low-enriched uranium in.

The primary tasks were the organization of industrial production of plutonium-239 and uranium-235. To solve the first problem, it was necessary to create experimental, and then industrial nuclear reactors, the construction of radiochemical and special metallurgical shops. To solve the second problem, the construction of a plant for the separation of uranium isotopes by the diffusion method was launched.
The solution of these problems turned out to be possible as a result of the creation of industrial technologies, the organization of production and the development of the necessary large quantities of pure metallic uranium, uranium oxide, uranium hexafluoride, other uranium compounds, high purity graphite and a number of other special materials, the creation of a complex of new industrial units and devices. The insufficient volume of uranium ore mining and the production of uranium concentrates in the USSR (the first plant for the production of uranium concentrate - "Combine No. 6 NKVD USSR" in Tajikistan was founded in 1945) during this period was compensated by trophy raw materials and products of uranium enterprises in Eastern Europe, with which the USSR entered into relevant agreements.
In 1945, the Government of the USSR made the following major decisions:
- on the creation on the basis of the Kirov Plant (Leningrad) of two special experimental design bureaus designed to develop equipment for the production of uranium enriched in the isotope 235 by the gaseous diffusion method;
- on the start of construction in the Middle Urals (near the village of Verkh-Neyvinsky) of a diffusion plant for the production of enriched uranium-235;
- on the organization of a laboratory for work on the creation of heavy water reactors on natural uranium;
- on the choice of a site and the start of construction in the South Urals of the country's first enterprise for the production of plutonium-239.
The structure of the enterprise in the South Urals was to include:
- uranium-graphite reactor on natural (natural) uranium (Plant "A");
- radiochemical production for the separation of plutonium-239 from natural (natural) uranium irradiated in the reactor (plant "B");
- chemical and metallurgical production for the production of high-purity metallic plutonium (Plant "B").
Participation of German specialists in the nuclear project

In 1945, hundreds of German scientists related to the nuclear problem were brought from Germany to the USSR. Most of them (about 300 people) were brought to Sukhumi and secretly placed in the former estates of Grand Duke Alexander Mikhailovich and the millionaire Smetsky (Sinop and Agudzery sanatoriums). Equipment was taken to the USSR from the German Institute of Chemistry and Metallurgy, the Kaiser Wilhelm Institute of Physics, Siemens electrical laboratories, and the Physical Institute of the German Post Office. Three of the four German cyclotrons, powerful magnets, electron microscopes, oscilloscopes, high voltage transformers, ultra-precise instruments were brought to the USSR. In November 1945, the Directorate of Special Institutes (9th Directorate of the NKVD of the USSR) was created as part of the NKVD of the USSR to manage the work on the use of German specialists.
Sanatorium "Sinop" was called "Object" A "" - it was led by Baron Manfred von Ardenne. "Agudzers" became "Object" G "" - it was headed by Gustav Hertz. Outstanding scientists worked at objects "A" and "G" - Nikolaus Riehl, Max Volmer, who built the first plant in the USSR for the production of heavy water, Peter Thyssen, designer of nickel filters for gas diffusion separation of isotopes uranium, Max Steenbeck and Gernot Zippe, who worked on centrifuge separation method and subsequently received patents for gas centrifuges in the west. On the basis of objects "A" and "G" was later created (SFTI).
Some leading German specialists were awarded USSR government awards for this work, including the Stalin Prize.
In the period 1954-1959, German specialists at different times moved to the GDR (Gernot Zippe - to Austria).

Construction of a gas diffusion plant in Novouralsk

In 1946, at the production base of plant No. 261 of the People's Commissariat of Aviation Industry in Novouralsk, the construction of a gas diffusion plant began, which was called Combine No. 813 (Plant D-1)) and intended for the production of highly enriched uranium. The plant gave the first production in 1949.

Construction of uranium hexafluoride production in Kirovo-Chepetsk

Over time, a whole complex of industrial enterprises, buildings and structures was erected on the site of the selected construction site, interconnected by a network of roads and railways, a system of heat and power supply, industrial water supply and sewerage. At different times, the secret city was called differently, but the most famous name is Chelyabinsk-40 or Sorokovka. At present, the industrial complex, which was originally called plant No. 817, is called the Mayak production association, and the city on the shore of Lake Irtyash, in which Mayak workers and their families live, was named Ozyorsk.
In November 1945, geological surveys began at the selected site, and from the beginning of December, the first builders began to arrive.
The first head of construction (1946-1947) was Ya. D. Rappoport, later he was replaced by Major General M. M. Tsarevsky. The chief construction engineer was V. A. Saprykin, the first director of the future enterprise was P. T. Bystrov (from April 17, 1946), who was replaced by E. P. Slavsky (from July 10, 1947), and then B. G Muzrukov (since December 1, 1947). I. V. Kurchatov was appointed scientific director of the plant.

Construction of Arzamas-16

Products

Development of the design of atomic bombs

Decree of the Council of Ministers of the USSR No. 1286-525ss "On the plan for the deployment of KB-11 at Laboratory No. 2 of the USSR Academy of Sciences" defined the first tasks of KB-11: the creation under the scientific supervision of Laboratory No. 2 (Academician I. V. Kurchatov) of atomic bombs, conventionally named in the decree "Jet engines C", in two versions: RDS-1 - an implosive type with plutonium and a cannon-type atomic bomb RDS-2 with uranium-235.
Tactical and technical specifications for the design of the RDS-1 and RDS-2 were to be developed by July 1, 1946, and the designs of their main components - by July 1, 1947. The fully manufactured RDS-1 bomb was to be presented for state tests for an explosion when installed on the ground by January 1, 1948, in an aviation version - by March 1, 1948, and the RDS-2 bomb - by June 1, 1948 and January 1, 1949, respectively. be carried out in parallel with the organization in KB-11 of special laboratories and the deployment of these laboratories. Such tight deadlines and the organization of parallel work also became possible due to the receipt in the USSR of some intelligence data on American atomic bombs.
Research laboratories and design departments of KB-11 began to expand their activities directly in

The one who invented the atomic bomb could not even imagine what tragic consequences this miracle invention of the 20th century could lead to. Before this superweapon was experienced by the inhabitants of the Japanese cities of Hiroshima and Nagasaki, a very long way had been done.
A start
In April 1903, Paul Langevin's friends gathered in the Parisian Garden of France. The reason was the defense of the dissertation of the young and talented scientist Marie Curie. Among the distinguished guests was the famous English physicist Sir Ernest Rutherford. In the midst of the fun, the lights were put out. announced to everyone that now there will be a surprise. With a solemn air, Pierre Curie brought in a small tube of radium salts, which shone with a green light, causing extraordinary delight among those present. In the future, the guests heatedly discussed the future of this phenomenon. Everyone agreed that thanks to radium, the acute problem of lack of energy would be solved. This inspired everyone to new research and further perspectives. If they had been told then that laboratory work with radioactive elements would lay the foundation for a terrible weapon of the 20th century, it is not known what their reaction would have been. It was then that the story of the atomic bomb began, which claimed the lives of hundreds of thousands of Japanese civilians.
Game ahead of the curve
On December 17, 1938, the German scientist Otto Gann obtained irrefutable evidence of the decay of uranium into smaller elementary particles. In fact, he managed to split the atom. In the scientific world, this was regarded as a new milestone in the history of mankind. Otto Gunn did not share the political views of the Third Reich. Therefore, in the same year, 1938, the scientist was forced to move to Stockholm, where, together with Friedrich Strassmann, he continued his scientific research. Fearing that fascist Germany will be the first to receive a terrible weapon, he writes a letter with a warning about this. The news of a possible lead greatly alarmed the US government. The Americans began to act quickly and decisively.
Who created the atomic bomb? American project
Even before the group, many of whom were refugees from the Nazi regime in Europe, was tasked with developing nuclear weapons. The initial research, it is worth noting, was carried out in Nazi Germany. In 1940, the government of the United States of America began funding its own program to develop atomic weapons. An incredible amount of two and a half billion dollars was allocated for the implementation of the project. Outstanding physicists of the 20th century were invited to carry out this secret project, including more than ten Nobel laureates. In total, about 130 thousand employees were involved, among whom were not only the military, but also civilians. The development team was led by Colonel Leslie Richard Groves, with Robert Oppenheimer as supervisor. He is the man who invented the atomic bomb. A special secret engineering building was built in the Manhattan area, which is known to us under the code name "Manhattan Project". Over the next few years, the scientists of the secret project worked on the problem of nuclear fission of uranium and plutonium.
Non-peaceful atom by Igor Kurchatov
Today, every schoolchild will be able to answer the question of who invented the atomic bomb in the Soviet Union. And then, in the early 30s of the last century, no one knew this.
In 1932, Academician Igor Vasilyevich Kurchatov was one of the first in the world to start studying the atomic nucleus. Gathering like-minded people around him, Igor Vasilievich in 1937 created the first cyclotron in Europe. In the same year, he and his like-minded people create the first artificial nuclei.
In 1939, I. V. Kurchatov began to study a new direction - nuclear physics. After several laboratory successes in studying this phenomenon, the scientist gets at his disposal a secret research center, which was named "Laboratory No. 2". Today, this secret object is called "Arzamas-16".
The target direction of this center was a serious research and development of nuclear weapons. Now it becomes obvious who created the atomic bomb in the Soviet Union. There were only ten people on his team then.
atomic bomb to be
By the end of 1945, Igor Vasilyevich Kurchatov managed to assemble a serious team of scientists numbering more than a hundred people. The best minds of various scientific specializations came to the laboratory from all over the country to create atomic weapons. After the Americans dropped the atomic bomb on Hiroshima, Soviet scientists realized that this could also be done with the Soviet Union. "Laboratory No. 2" receives a sharp increase in funding from the country's leadership and a large influx of qualified personnel. Lavrenty Pavlovich Beria is appointed responsible for such an important project. The enormous labors of Soviet scientists have borne fruit.
Semipalatinsk test site
The atomic bomb in the USSR was first tested at the test site in Semipalatinsk (Kazakhstan). On August 29, 1949, a 22 kiloton nuclear device shook the Kazakh land. Nobel laureate physicist Otto Hanz said: “This is good news. If Russia has atomic weapons, then there will be no war.” It was this atomic bomb in the USSR, encrypted as product number 501, or RDS-1, that eliminated the US monopoly on nuclear weapons.
Atomic bomb. Year 1945
In the early morning of July 16, the Manhattan Project conducted its first successful test of an atomic device - a plutonium bomb - at the Alamogordo test site in New Mexico, USA.
The money invested in the project was well spent. The first in the history of mankind was produced at 5:30 in the morning.
"We have done the work of the devil," the one who invented the atomic bomb in the United States, later called the "father of the atomic bomb," will say later.
Japan does not capitulate
By the time of the final and successful testing of the atomic bomb, Soviet troops and allies had finally defeated Nazi Germany. However, there was one state that promised to fight to the end for dominance in the Pacific Ocean. From mid-April to mid-July 1945, the Japanese army repeatedly carried out air strikes against allied forces, thereby inflicting heavy losses on the US army. At the end of July 1945, the militarist government of Japan rejected the Allied demand for surrender in accordance with the Potsdam Declaration. In it, in particular, it was said that in case of disobedience, the Japanese army would face rapid and complete destruction.
President agrees
The American government kept its word and began targeted bombing of Japanese military positions. Air strikes did not bring the desired result, and US President Harry Truman decides on the invasion of American troops into Japan. However, the military command dissuades its president from such a decision, citing the fact that the American invasion would entail a large number of victims.
At the suggestion of Henry Lewis Stimson and Dwight David Eisenhower, it was decided to use a more effective way to end the war. A big supporter of the atomic bomb, US Presidential Secretary James Francis Byrnes, believed that the bombing of Japanese territories would finally end the war and put the US in a dominant position, which would positively affect the future course of events in the post-war world. Thus, US President Harry Truman was convinced that this was the only correct option.
Atomic bomb. Hiroshima
The small Japanese city of Hiroshima, with a population of just over 350,000, was chosen as the first target, located five hundred miles from the capital of Japan, Tokyo. After the modified Enola Gay B-29 bomber arrived at the US naval base on Tinian Island, an atomic bomb was installed on board the aircraft. Hiroshima was supposed to experience the effects of 9,000 pounds of uranium-235.
This hitherto unseen weapon was intended for civilians in a small Japanese town. The bomber commander was Colonel Paul Warfield Tibbets, Jr. The US atomic bomb bore the cynical name "Baby". On the morning of August 6, 1945, at about 8:15 am, the American "Baby" was dropped on the Japanese Hiroshima. About 15 thousand tons of TNT destroyed all life within a radius of five square miles. One hundred and forty thousand inhabitants of the city died in a matter of seconds. The surviving Japanese died a painful death from radiation sickness.
They were destroyed by the American atomic "Kid". However, the devastation of Hiroshima did not cause the immediate surrender of Japan, as everyone expected. Then it was decided to another bombardment of Japanese territory.
Nagasaki. Sky on fire
The American atomic bomb "Fat Man" was installed on board the B-29 aircraft on August 9, 1945, all in the same place, at the US naval base in Tinian. This time the aircraft commander was Major Charles Sweeney. Initially, the strategic target was the city of Kokura.
However, the weather conditions did not allow to carry out the plan, a lot of clouds interfered. Charles Sweeney went into the second round. At 11:02 am, the American nuclear-powered Fat Man swallowed up Nagasaki. It was a more powerful destructive air strike, which, in its strength, was several times higher than the bombing in Hiroshima. Nagasaki tested an atomic weapon weighing about 10,000 pounds and 22 kilotons of TNT.
The geographical location of the Japanese city reduced the expected effect. The thing is that the city is located in a narrow valley between the mountains. Therefore, the destruction of 2.6 square miles did not reveal the full potential of American weapons. The Nagasaki atomic bomb test is considered the failed "Manhattan Project".
Japan surrendered
On the afternoon of August 15, 1945, Emperor Hirohito announced his country's surrender in a radio address to the people of Japan. This news quickly spread around the world. In the United States of America, celebrations began on the occasion of the victory over Japan. The people rejoiced.
On September 2, 1945, a formal agreement to end the war was signed aboard the USS Missouri, anchored in Tokyo Bay. Thus ended the most brutal and bloody war in the history of mankind.
For six long years, the world community has been moving towards this significant date - since September 1, 1939, when the first shots of Nazi Germany were fired on the territory of Poland.
Peaceful atom
A total of 124 nuclear explosions were carried out in the Soviet Union. It is characteristic that all of them were carried out for the benefit of the national economy. Only three of them were accidents involving the release of radioactive elements. Programs for the use of peaceful atom were implemented only in two countries - the United States and the Soviet Union. The peaceful nuclear power industry also knows an example of a global catastrophe, when a reactor exploded at the fourth power unit of the Chernobyl nuclear power plant.

The world of the atom is so fantastic that its understanding requires a radical break in the usual concepts of space and time. Atoms are so small that if a drop of water could be enlarged to the size of the Earth, each atom in that drop would be smaller than an orange. In fact, one drop of water is made up of 6000 billion billion (6000000000000000000000) hydrogen and oxygen atoms. And yet, despite its microscopic size, the atom has a structure to some extent similar to the structure of our solar system. In its incomprehensibly small center, the radius of which is less than one trillionth of a centimeter, is a relatively huge "sun" - the nucleus of an atom.

Around this atomic "sun" tiny "planets" - electrons - revolve. The nucleus consists of two main building blocks of the Universe - protons and neutrons (they have a unifying name - nucleons). An electron and a proton are charged particles, and the amount of charge in each of them is exactly the same, but the charges differ in sign: the proton is always positively charged, and the electron is always negative. The neutron does not carry an electric charge and therefore has a very high permeability.

In the atomic measurement scale, the mass of the proton and neutron is taken as unity. The atomic weight of any chemical element therefore depends on the number of protons and neutrons contained in its nucleus. For example, a hydrogen atom, whose nucleus consists of only one proton, has an atomic mass of 1. A helium atom, with a nucleus of two protons and two neutrons, has an atomic mass of 4.

The nuclei of atoms of the same element always contain the same number of protons, but the number of neutrons may be different. Atoms that have nuclei with the same number of protons, but differ in the number of neutrons and related to varieties of the same element, are called isotopes. To distinguish them from each other, a number equal to the sum of all particles in the nucleus of a given isotope is assigned to the element symbol.

The question may arise: why does the nucleus of an atom not fall apart? After all, the protons included in it are electrically charged particles with the same charge, which must repel each other with great force. This is explained by the fact that inside the nucleus there are also so-called intranuclear forces that attract the particles of the nucleus to each other. These forces compensate for the repulsive forces of protons and do not allow the nucleus to fly apart spontaneously.

The intranuclear forces are very strong, but they act only at very close range. Therefore, nuclei of heavy elements, consisting of hundreds of nucleons, turn out to be unstable. The particles of the nucleus are in constant motion here (within the volume of the nucleus), and if you add some additional amount of energy to them, they can overcome internal forces - the nucleus will be divided into parts. The amount of this excess energy is called the excitation energy. Among the isotopes of heavy elements, there are those that seem to be on the very verge of self-decay. Only a small "push" is enough, for example, a simple hit in the nucleus of a neutron (and it does not even have to be accelerated to a high speed) for the nuclear fission reaction to start. Some of these "fissile" isotopes were later made artificially. In nature, there is only one such isotope - it is uranium-235.

Uranus was discovered in 1783 by Klaproth, who isolated it from uranium pitch and named it after the recently discovered planet Uranus. As it turned out later, it was, in fact, not uranium itself, but its oxide. Pure uranium, a silvery-white metal, was obtained
only in 1842 Peligot. The new element did not have any remarkable properties and did not attract attention until 1896, when Becquerel discovered the phenomenon of radioactivity of uranium salts. After that, uranium became the object of scientific research and experiments, but still had no practical application.

When, in the first third of the 20th century, the structure of the atomic nucleus more or less became clear to physicists, they first of all tried to fulfill the old dream of alchemists - they tried to turn one chemical element into another. In 1934, the French researchers, the spouses Frederic and Irene Joliot-Curie, reported to the French Academy of Sciences about the following experiment: when aluminum plates were bombarded with alpha particles (nuclei of the helium atom), aluminum atoms turned into phosphorus atoms, but not ordinary, but radioactive, which, in turn, passed into a stable isotope of silicon. Thus, an aluminum atom, having added one proton and two neutrons, turned into a heavier silicon atom.

This experience led to the idea that if the nuclei of the heaviest element existing in nature, uranium, are “shelled” with neutrons, then one can obtain an element that does not exist in natural conditions. In 1938, the German chemists Otto Hahn and Fritz Strassmann repeated in general terms the experience of the Joliot-Curie spouses, taking uranium instead of aluminum. The results of the experiment were not at all what they expected - instead of a new superheavy element with a mass number greater than that of uranium, Hahn and Strassmann received light elements from the middle part of the periodic system: barium, krypton, bromine and some others. The experimenters themselves could not explain the observed phenomenon. It was not until the following year that the physicist Lisa Meitner, to whom Hahn reported her difficulties, found a correct explanation for the observed phenomenon, suggesting that when uranium was bombarded with neutrons, its nucleus split (fissioned). In this case, nuclei of lighter elements should have been formed (this is where barium, krypton and other substances came from), and 2-3 free neutrons should have been released. Further research allowed to clarify in detail the picture of what is happening.

Natural uranium consists of a mixture of three isotopes with masses 238, 234 and 235. The main amount of uranium falls on the isotope-238, the nucleus of which includes 92 protons and 146 neutrons. Uranium-235 is only 1/140 of natural uranium (0.7% (it has 92 protons and 143 neutrons in its nucleus), and uranium-234 (92 protons, 142 neutrons) is only 1/17500 of the total mass of uranium (0 006% The least stable of these isotopes is uranium-235.

From time to time, the nuclei of its atoms spontaneously divide into parts, as a result of which lighter elements of the periodic system are formed. The process is accompanied by the release of two or three free neutrons, which rush at a tremendous speed - about 10 thousand km / s (they are called fast neutrons). These neutrons can hit other uranium nuclei, causing nuclear reactions. Each isotope behaves differently in this case. Uranium-238 nuclei in most cases simply capture these neutrons without any further transformations. But in about one case out of five, when a fast neutron collides with the nucleus of the 238 isotope, a curious nuclear reaction occurs: one of the uranium-238 neutrons emits an electron, turning into a proton, that is, the uranium isotope turns into more
the heavy element is neptunium-239 (93 protons + 146 neutrons). But neptunium is unstable - after a few minutes one of its neutrons emits an electron, turning into a proton, after which the neptunium isotope turns into the next element of the periodic system - plutonium-239 (94 protons + 145 neutrons). If a neutron enters the nucleus of unstable uranium-235, then fission immediately occurs - the atoms decay with the emission of two or three neutrons. It is clear that in natural uranium, most of whose atoms belong to the 238 isotope, this reaction has no visible consequences - all free neutrons will eventually be absorbed by this isotope.

But what if we imagine a fairly massive piece of uranium, consisting entirely of the 235 isotope?

Here the process will go differently: the neutrons released during the fission of several nuclei, in turn, falling into neighboring nuclei, cause their fission. As a result, a new portion of neutrons is released, which splits the following nuclei. Under favorable conditions, this reaction proceeds like an avalanche and is called a chain reaction. A few bombarding particles may suffice to start it.

Indeed, let only 100 neutrons bombard uranium-235. They will split 100 uranium nuclei. In this case, 250 new neutrons of the second generation will be released (an average of 2.5 per fission). The neutrons of the second generation will already produce 250 fissions, at which 625 neutrons will be released. In the next generation it will be 1562, then 3906, then 9670, and so on. The number of divisions will increase without limit if the process is not stopped.

However, in reality, only an insignificant part of neutrons gets into the nuclei of atoms. The rest, swiftly rushing between them, are carried away into the surrounding space. A self-sustaining chain reaction can only occur in a sufficiently large array of uranium-235, which is said to have a critical mass. (This mass under normal conditions is 50 kg.) It is important to note that the fission of each nucleus is accompanied by the release of a huge amount of energy, which turns out to be about 300 million times more than the energy spent on fission! (It has been calculated that with the complete fission of 1 kg of uranium-235, the same amount of heat is released as when burning 3 thousand tons of coal.)

This colossal surge of energy, released in a matter of moments, manifests itself as an explosion of monstrous force and underlies the operation of nuclear weapons. But in order for this weapon to become a reality, it is necessary that the charge does not consist of natural uranium, but of a rare isotope - 235 (such uranium is called enriched). Later it was found that pure plutonium is also a fissile material and can be used in an atomic charge instead of uranium-235.

All these important discoveries were made on the eve of World War II. Soon secret work began in Germany and other countries on the creation of an atomic bomb. In the United States, this problem was taken up in 1941. The whole complex of works was given the name of the "Manhattan Project".

The administrative leadership of the project was carried out by General Groves, and the scientific direction was carried out by Professor Robert Oppenheimer of the University of California. Both were well aware of the enormous complexity of the task before them. Therefore, Oppenheimer's first concern was the acquisition of a highly intelligent scientific team. In the United States at that time there were many physicists who had emigrated from fascist Germany. It was not easy to involve them in the creation of weapons directed against their former homeland. Oppenheimer spoke to everyone personally, using the full force of his charm. Soon he managed to gather a small group of theorists, whom he jokingly called "luminaries." And in fact, it included the largest experts of that time in the field of physics and chemistry. (Among them are 13 Nobel Prize winners, including Bohr, Fermi, Frank, Chadwick, Lawrence.) In addition to them, there were many other specialists of various profiles.

The US government did not skimp on spending, and from the very beginning the work assumed a grandiose scope. In 1942, the world's largest research laboratory was founded at Los Alamos. The population of this scientific city soon reached 9 thousand people. In terms of the composition of scientists, the scope of scientific experiments, the number of specialists and workers involved in the work, the Los Alamos Laboratory had no equal in world history. The Manhattan Project had its own police, counterintelligence, communications system, warehouses, settlements, factories, laboratories, and its own colossal budget.

The main goal of the project was to obtain enough fissile material from which to create several atomic bombs. In addition to uranium-235, as already mentioned, the artificial element plutonium-239 could serve as a charge for the bomb, that is, the bomb could be either uranium or plutonium.

Groves and Oppenheimer agreed that work should be carried out simultaneously in two directions, since it is impossible to decide in advance which of them will be more promising. Both methods were fundamentally different from each other: the accumulation of uranium-235 had to be carried out by separating it from the bulk of natural uranium, and plutonium could only be obtained as a result of a controlled nuclear reaction by irradiating uranium-238 with neutrons. Both paths seemed unusually difficult and did not promise easy solutions.

Indeed, how can two isotopes be separated from each other, which differ only slightly in their weight and chemically behave in exactly the same way? Neither science nor technology has ever faced such a problem. Plutonium production also seemed very problematic at first. Prior to this, the entire experience of nuclear transformations was reduced to several laboratory experiments. Now it was necessary to master the production of kilograms of plutonium on an industrial scale, develop and create a special installation for this - a nuclear reactor, and learn how to control the course of a nuclear reaction.

And here and there a whole complex of complex problems had to be solved. Therefore, the "Manhattan Project" consisted of several subprojects, headed by prominent scientists. Oppenheimer himself was the head of the Los Alamos Science Laboratory. Lawrence was in charge of the Radiation Laboratory at the University of California. Fermi led research at the University of Chicago on the creation of a nuclear reactor.

Initially, the most important problem was obtaining uranium. Before the war, this metal actually had no use. Now that it was needed immediately in huge quantities, it turned out that there was no industrial way to produce it.

The Westinghouse company undertook its development and quickly achieved success. After purification of uranium resin (in this form uranium occurs in nature) and obtaining uranium oxide, it was converted into tetrafluoride (UF4), from which metallic uranium was isolated by electrolysis. If at the end of 1941, American scientists had only a few grams of metallic uranium at their disposal, then in November 1942 its industrial production at the Westinghouse plants reached 6,000 pounds per month.

At the same time, work was underway on the creation of a nuclear reactor. The plutonium production process actually boiled down to the irradiation of uranium rods with neutrons, as a result of which part of the uranium-238 had to turn into plutonium. Sources of neutrons in this case could be fissile uranium-235 atoms scattered in sufficient quantities among uranium-238 atoms. But in order to maintain a constant reproduction of neutrons, a chain reaction of fission of uranium-235 atoms had to begin. Meanwhile, as already mentioned, for every atom of uranium-235 there were 140 atoms of uranium-238. It is clear that the neutrons flying in all directions were much more likely to meet exactly them on their way. That is, a huge number of released neutrons turned out to be absorbed by the main isotope to no avail. Obviously, under such conditions, the chain reaction could not go. How to be?

At first it seemed that without the separation of two isotopes, the operation of the reactor was generally impossible, but one important circumstance was soon established: it turned out that uranium-235 and uranium-238 were susceptible to neutrons of different energies. It is possible to split the nucleus of an atom of uranium-235 with a neutron of relatively low energy, having a speed of about 22 m/s. Such slow neutrons are not captured by uranium-238 nuclei - for this they must have a speed of the order of hundreds of thousands of meters per second. In other words, uranium-238 is powerless to prevent the start and progress of a chain reaction in uranium-235 caused by neutrons slowed down to extremely low speeds - no more than 22 m/s. This phenomenon was discovered by the Italian physicist Fermi, who lived in the United States since 1938 and supervised the work on the creation of the first reactor here. Fermi decided to use graphite as a neutron moderator. According to his calculations, the neutrons emitted from uranium-235, having passed through a layer of graphite of 40 cm, should have reduced their speed to 22 m/s and started a self-sustaining chain reaction in uranium-235.

The so-called "heavy" water could serve as another moderator. Since the hydrogen atoms that make up it are very close in size and mass to neutrons, they could best slow them down. (About the same thing happens with fast neutrons as with balls: if a small ball hits a large one, it rolls back, almost without losing speed, but when it meets a small ball, it transfers a significant part of its energy to it - just like a neutron in an elastic collision bounces off a heavy nucleus only slightly slowing down, and on collision with the nuclei of hydrogen atoms loses all its energy very quickly.) However, ordinary water is not suitable for slowing down, since its hydrogen tends to absorb neutrons. That is why deuterium, which is part of "heavy" water, should be used for this purpose.

In early 1942, under the leadership of Fermi, construction began on the first ever nuclear reactor in the tennis court under the west stands of the Chicago Stadium. All work was carried out by the scientists themselves. The reaction can be controlled in the only way - by adjusting the number of neutrons involved in the chain reaction. Fermi envisioned doing this with rods made from materials such as boron and cadmium, which absorb neutrons strongly. Graphite bricks served as a moderator, from which physicists erected columns 3 m high and 1.2 m wide. Rectangular blocks with uranium oxide were installed between them. About 46 tons of uranium oxide and 385 tons of graphite went into the entire structure. To slow down the reaction, cadmium and boron rods introduced into the reactor served.

If this weren't enough, then for insurance, on a platform located above the reactor, there were two scientists with buckets filled with a solution of cadmium salts - they were supposed to pour them over the reactor if the reaction got out of control. Fortunately, this was not required. On December 2, 1942, Fermi ordered all the control rods to be extended, and the experiment began. Four minutes later, the neutron counters began to click louder and louder. With every minute, the intensity of the neutron flux became greater. This indicated that a chain reaction was taking place in the reactor. It went on for 28 minutes. Then Fermi signaled, and the lowered rods stopped the process. Thus, for the first time, man released the energy of the atomic nucleus and proved that he could control it at will. Now there was no longer any doubt that nuclear weapons were a reality.

In 1943, the Fermi reactor was dismantled and transported to the Aragonese National Laboratory (50 km from Chicago). Was here shortly
another nuclear reactor was built, in which heavy water was used as a moderator. It consisted of a cylindrical aluminum tank containing 6.5 tons of heavy water, into which 120 rods of uranium metal were vertically loaded, enclosed in an aluminum shell. The seven control rods were made from cadmium. Around the tank was a graphite reflector, then a screen made of lead and cadmium alloys. The entire structure was enclosed in a concrete shell with a wall thickness of about 2.5 m.

Experiments at these experimental reactors confirmed the possibility of industrial production of plutonium.

The main center of the "Manhattan Project" soon became the town of Oak Ridge in the Tennessee River Valley, whose population in a few months grew to 79 thousand people. Here, in a short time, the first plant for the production of enriched uranium was built. Immediately in 1943, an industrial reactor was launched that produced plutonium. In February 1944, about 300 kg of uranium was extracted from it daily, from the surface of which plutonium was obtained by chemical separation. (To do this, the plutonium was first dissolved and then precipitated.) The purified uranium was then returned to the reactor again. In the same year, in the barren, desolate desert on the south bank of the Columbia River, construction began on the huge Hanford Plant. Three powerful nuclear reactors were located here, giving several hundred grams of plutonium daily.

In parallel, research was in full swing to develop an industrial process for uranium enrichment.

After considering different options, Groves and Oppenheimer decided to focus on two methods: gas diffusion and electromagnetic.

The gas diffusion method was based on a principle known as Graham's law (it was first formulated in 1829 by the Scottish chemist Thomas Graham and developed in 1896 by the English physicist Reilly). In accordance with this law, if two gases, one of which is lighter than the other, are passed through a filter with negligibly small openings, then a little more light gas will pass through it than heavy gas. In November 1942, Urey and Dunning at Columbia University created a gaseous diffusion method for separating uranium isotopes based on the Reilly method.

Since natural uranium is a solid, it was first converted to uranium fluoride (UF6). This gas was then passed through microscopic - on the order of thousandths of a millimeter - holes in the filter septum.

Since the difference in the molar weights of the gases was very small, behind the baffle the content of uranium-235 increased only by a factor of 1.0002.

In order to increase the amount of uranium-235 even more, the resulting mixture is again passed through a partition, and the amount of uranium is again increased by 1.0002 times. Thus, in order to increase the content of uranium-235 to 99%, it was necessary to pass the gas through 4000 filters. This took place in a huge gaseous diffusion plant at Oak Ridge.

In 1940, under the leadership of Ernst Lawrence at the University of California, research began on the separation of uranium isotopes by the electromagnetic method. It was necessary to find such physical processes that would allow isotopes to be separated using the difference in their masses. Lawrence made an attempt to separate isotopes using the principle of a mass spectrograph - an instrument that determines the masses of atoms.

The principle of its operation was as follows: pre-ionized atoms were accelerated by an electric field and then passed through a magnetic field in which they described circles located in a plane perpendicular to the direction of the field. Since the radii of these trajectories were proportional to the mass, the light ions ended up on circles of a smaller radius than the heavy ones. If traps were placed in the path of the atoms, then it was possible in this way to separately collect different isotopes.

That was the method. Under laboratory conditions, he gave good results. But the construction of a plant in which isotope separation could be carried out on an industrial scale proved to be extremely difficult. However, Lawrence eventually managed to overcome all difficulties. The result of his efforts was the appearance of the calutron, which was installed in a giant plant in Oak Ridge.

This electromagnetic plant was built in 1943 and turned out to be perhaps the most expensive brainchild of the Manhattan Project. Lawrence's method required a large number of complex, as yet undeveloped devices involving high voltage, high vacuum, and strong magnetic fields. The costs were enormous. Calutron had a giant electromagnet, the length of which reached 75 m and weighed about 4000 tons.

Several thousand tons of silver wire went into the windings for this electromagnet.

The entire work (excluding the cost of $300 million worth of silver, which the State Treasury provided only temporarily) cost $400 million. Only for the electricity spent by the calutron, the Ministry of Defense paid 10 million. Much of the equipment at the Oak Ridge factory was superior in scale and precision to anything ever developed in the field.

But all these expenses were not in vain. Having spent a total of about 2 billion dollars, US scientists by 1944 created a unique technology for uranium enrichment and plutonium production. Meanwhile, at the Los Alamos Laboratory, they were working on the design of the bomb itself. The principle of its operation was in general terms clear for a long time: the fissile substance (plutonium or uranium-235) should have been transferred to a critical state at the time of the explosion (for a chain reaction to occur, the mass of the charge must be even noticeably larger than the critical one) and irradiated with a neutron beam, which entailed is the start of a chain reaction.

According to calculations, the critical mass of the charge exceeded 50 kilograms, but it could be significantly reduced. In general, the magnitude of the critical mass is strongly influenced by several factors. The larger the surface area of the charge, the more neutrons are emitted uselessly into the surrounding space. A sphere has the smallest surface area. Consequently, spherical charges, other things being equal, have the smallest critical mass. In addition, the value of the critical mass depends on the purity and type of fissile materials. It is inversely proportional to the square of the density of this material, which allows, for example, by doubling the density, to reduce the critical mass by a factor of four. The required degree of subcriticality can be obtained, for example, by compacting the fissile material due to the explosion of a conventional explosive charge made in the form of a spherical shell surrounding the nuclear charge. The critical mass can also be reduced by surrounding the charge with a screen that reflects neutrons well. Lead, beryllium, tungsten, natural uranium, iron, and many others can be used as such a screen.

One of the possible designs of the atomic bomb consists of two pieces of uranium, which, when combined, form a mass greater than the critical one. In order to cause a bomb explosion, you need to bring them together as quickly as possible. The second method is based on the use of an inward-converging explosion. In this case, the flow of gases from a conventional explosive was directed at the fissile material located inside and compressing it until it reached a critical mass. The connection of the charge and its intense irradiation with neutrons, as already mentioned, causes a chain reaction, as a result of which, in the first second, the temperature rises to 1 million degrees. During this time, only about 5% of the critical mass managed to separate. The rest of the charge in early bomb designs evaporated without
any good.

The first atomic bomb in history (it was given the name "Trinity") was assembled in the summer of 1945. And on June 16, 1945, the first atomic explosion on Earth was carried out at the nuclear test site in the Alamogordo desert (New Mexico). The bomb was placed in the center of the test site on top of a 30-meter steel tower. Recording equipment was placed around it at a great distance. At 9 km there was an observation post, and at 16 km - a command post. The atomic explosion made a tremendous impression on all the witnesses of this event. According to the description of eyewitnesses, there was a feeling that many suns merged into one and lit up the polygon at once. Then a huge ball of fire appeared above the plain, and a round cloud of dust and light began to slowly and ominously rise towards it.

After taking off from the ground, this fireball flew up to a height of more than three kilometers in a few seconds. With every moment it grew in size, soon its diameter reached 1.5 km, and it slowly rose into the stratosphere. The fireball then gave way to a column of swirling smoke, which stretched out to a height of 12 km, taking the form of a giant mushroom. All this was accompanied by a terrible roar, from which the earth trembled. The power of the exploded bomb exceeded all expectations.

As soon as the radiation situation allowed, several Sherman tanks, lined with lead plates from the inside, rushed into the explosion area. On one of them was Fermi, who was eager to see the results of his work. Dead scorched earth appeared before his eyes, on which all life was destroyed within a radius of 1.5 km. The sand sintered into a glassy greenish crust that covered the ground. In a huge crater lay the mutilated remains of a steel support tower. The force of the explosion was estimated at 20,000 tons of TNT.

The next step was to be the combat use of the bomb against Japan, which, after the surrender of fascist Germany, alone continued the war with the United States and its allies. There were no launch vehicles then, so the bombing had to be carried out from an aircraft. The components of the two bombs were transported with great care by the USS Indianapolis to Tinian Island, where the US Air Force 509th Composite Group was based. By type of charge and design, these bombs were somewhat different from each other.

The first bomb - "Baby" - was a large-sized aerial bomb with an atomic charge of highly enriched uranium-235. Its length was about 3 m, diameter - 62 cm, weight - 4.1 tons.

The second bomb - "Fat Man" - with a charge of plutonium-239 had an egg shape with a large-sized stabilizer. Its length
was 3.2 m, diameter 1.5 m, weight - 4.5 tons.

On August 6, Colonel Tibbets' B-29 Enola Gay bomber dropped the "Kid" on the large Japanese city of Hiroshima. The bomb was dropped by parachute and exploded, as it was planned, at an altitude of 600 m from the ground.

The consequences of the explosion were terrible. Even on the pilots themselves, the sight of the peaceful city destroyed by them in an instant made a depressing impression. Later, one of them admitted that they saw at that moment the worst thing that a person can see.

For those who were on earth, what was happening looked like a real hell. First of all, a heat wave passed over Hiroshima. Its action lasted only a few moments, but it was so powerful that it melted even tiles and quartz crystals in granite slabs, turned telephone poles into coal at a distance of 4 km and, finally, so incinerated human bodies that only shadows remained of them on the pavement asphalt. or on the walls of houses. Then a monstrous gust of wind escaped from under the fireball and rushed over the city at a speed of 800 km / h, sweeping away everything in its path. The houses that could not withstand his furious onslaught collapsed as if they had been cut down. In a giant circle with a diameter of 4 km, not a single building remained intact. A few minutes after the explosion, a black radioactive rain fell over the city - this moisture turned into steam condensed in the high layers of the atmosphere and fell to the ground in the form of large drops mixed with radioactive dust.

After the rain, a new gust of wind hit the city, this time blowing in the direction of the epicenter. He was weaker than the first, but still strong enough to uproot trees. The wind fanned a gigantic fire in which everything that could burn was burning. Of the 76,000 buildings, 55,000 were completely destroyed and burned down. Witnesses of this terrible catastrophe recalled people-torches from which burnt clothes fell to the ground along with tatters of skin, and crowds of distraught people, covered with terrible burns, who rushed screaming through the streets. There was a suffocating stench of burnt human flesh in the air. People lay everywhere, dead and dying. There were many who were blind and deaf and, poking in all directions, could not make out anything in the chaos that reigned around.

The unfortunate, who were from the epicenter at a distance of up to 800 m, burned out in a split second in the literal sense of the word - their insides evaporated, and their bodies turned into lumps of smoking coals. Located at a distance of 1 km from the epicenter, they were struck by radiation sickness in an extremely severe form. Within a few hours, they began to vomit severely, the temperature jumped to 39-40 degrees, shortness of breath and bleeding appeared. Then, non-healing ulcers appeared on the skin, the composition of the blood changed dramatically, and the hair fell out. After terrible suffering, usually on the second or third day, death occurred.

In total, about 240 thousand people died from the explosion and radiation sickness. About 160 thousand received radiation sickness in a milder form - their painful death was delayed for several months or years. When the news of the catastrophe spread throughout the country, all of Japan was paralyzed with fear. It increased even more after Major Sweeney's Box Car aircraft dropped a second bomb on Nagasaki on August 9th. Several hundred thousand inhabitants were also killed and wounded here. Unable to resist the new weapons, the Japanese government capitulated - the atomic bomb put an end to World War II.

War is over. It lasted only six years, but managed to change the world and people almost beyond recognition.

Human civilization before 1939 and human civilization after 1945 are strikingly different from each other. There are many reasons for this, but one of the most important is the emergence of nuclear weapons. It can be said without exaggeration that the shadow of Hiroshima lies over the entire second half of the 20th century. It became a deep moral burn for many millions of people, both those who were contemporaries of this catastrophe and those born decades after it. Modern man can no longer think about the world the way it was thought before August 6, 1945 - he understands too clearly that this world can turn into nothing in a few moments.

A modern person cannot look at the war, as his grandfathers and great-grandfathers watched - he knows for sure that this war will be the last, and there will be neither winners nor losers in it. Nuclear weapons have left their mark on all spheres of public life, and modern civilization cannot live by the same laws as sixty or eighty years ago. No one understood this better than the creators of the atomic bomb themselves.

"People of our planet Robert Oppenheimer wrote, should unite. The horror and destruction sown by the last war dictate this thought to us. Explosions of atomic bombs proved it with all cruelty. Other people at other times have said similar words - only about other weapons and other wars. They didn't succeed. But whoever says today that these words are useless is deceived by the vicissitudes of history. We cannot be convinced of this. The results of our labor leave no other choice for humanity but to create a unified world. A world based on law and humanism."

Scientists who created nuclear weapons. Creation of the atomic bomb in the USSR

Igor Kurchatov: short biography

The era before Kurchatov

Research during the Great Patriotic War

RDS-1, the first Russian atomic bomb

Uranium deficiency

Nuclear reactor start-up experiment

Successful bomb tests

Consequences of the explosion

"Fathers" of the atomic bomb

Short biography of Robert Oppenheimer

Encyclopedic YouTube

Work in 1941-1943

Foreign intelligence information

Participation of German specialists in the nuclear project

Construction of a gas diffusion plant in Novouralsk

Construction of uranium hexafluoride production in Kirovo-Chepetsk

Construction of Arzamas-16

Products

Development of the design of atomic bombs

A start

Game ahead of the curve

Non-peaceful atom by Igor Kurchatov

atomic bomb to be

Semipalatinsk test site

Atomic bomb. Year 1945

Japan does not capitulate

President agrees

Atomic bomb. Hiroshima

Nagasaki. Sky on fire

Japan surrendered

Peaceful atom