MAUD commission

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First page of the report of the MAUD commission, March 1941

The MAUD Commission ( English MAUD Committee ), officially the Military Application of Uranium Detonation , was an association of British scientists that existed from April 1940 to March 1941 and dealt with the possibility of building an atomic bomb. The Commission's reports were of great importance in relation to the later decision to build the first atomic bomb as part of the Manhattan Project .

The formation of the commission in response to the Frisch and Peierls memorandum

The commission was set up in response to a memorandum ( Frisch-Peierls-Memorandum ) drawn up in March 1940 by the German-Austrian emigrants Otto Frisch and Rudolf Peierls working at the University of Birmingham . In their memorandum, Frisch and Peierls discussed the latest advances in nuclear fission and warned strongly of the possibility of Hitler's Germany building a uranium bomb. This as "strictly confidential" (strictly confidential) Memorandum marked was by Marcus Oliphant , the supervisor of fresh and Peierls to Henry Tizard passed. Tizard was chairman of the British Aeronautical Research Committee , which had played a decisive role in the development of the radar before the war began . He recognized the importance of the "uranium problem" and called together the most important nuclear physicists in the country. The constituent meeting of the commission took place on April 10, 1940.

Members of the Commission

The members of the (strictly kept secret) commission were:

Frisch and Peierls were not accepted into the commission, although their memorandum had led to the formation of the same. Officially, they were considered "enemy aliens" and their participation was classified as a security risk. Later both made important contributions in Los Alamos as part of the British contribution to the construction of the first atomic bomb.

The naming: Miss Maud Rey at Kent

In April 1940 Denmark was occupied by German troops . Shortly afterwards, Niels Bohr wrote a letter from Copenhagen to his former colleague Frisch, which spoke of a "Miss Maud Rey at Kent". This Miss Rey could not be found at first, so that the assumption arose that Bohr had wanted to transmit an encrypted message to the German military censorship. On closer inspection, it was found that the letters for the words " Radium taken " ( Radium confiscated , "M i ss Maud R ey at Ken t") were hidden. This alarmed those involved in Birmingham, as they suspected that the German occupiers had confiscated the radioactive material stored in the Copenhagen Institute and that Germany may already be working at full speed on the development of nuclear weapons. The British commission was named " MAUD Committee " from this ominous news of Bohr's and kept it later when the addressee of the letter, Miss Maud Rey, the former English governess of Bohr's children, was found.

First decisions by the Commission

At the first meeting, a research program on isotope separation and nuclear fission was decided. In June 1940, the German emigrant Franz Eugen ("Francis") Simon , who worked in Cambridge, was commissioned to develop a method for isotope separation of 235 U and 238 U by gas diffusion. Ralph Howard Fowler was supposed to pass the progress in this research area on to the American Advisory Committee on Uranium , which was founded in 1939 under the leadership of Lyman Briggs . Simon submitted a report on his work on isotope separation in December 1940, which came to the conclusion that a separation of the two uranium isotopes 235 U and 238 U was possible in this way. Simon's report to the MAUD commission also contained estimates of the effort and costs of such an isotope separation and it became clear that a very large facility would be required for this. James Chadwick, one of the members of the MAUD commission later wrote: " I realized that a nuclear bomb was not only possible, it was inevitable " - I realized that a nuclear bomb was not only possible, but that it would inevitably come . And further: " I had then to start taking sleeping pills. It was the only remedy. “- From then on I had to take sleeping pills; without it no longer worked.

In March 1941, scientists at the Department of Terrestrial Magnetism (DTM) of the Carnegie Institution determined the cross section for fast neutrons of 235 U. With this data Peierls calculated the critical mass of 235 U to be about 9 kg in spherical form or 4.5 to 5 kg if the mass was surrounded by a neutron reflector . A report was in turn drawn up by the MAUD commission, a copy of which was also sent to Briggs Advisory Committee on Uranium in the United States.

Final reports from the Commission

On July 15, 1941, the MAUD commission submitted two reports. The first report was entitled Use of Uranium for a Bomb (using uranium for a bomb) and the second use of uranium as a source of power (use of uranium as an energy source) . In the first report it was stated that a bomb was possible in principle and the technical details of the construction were discussed. The required amount of fissile material was estimated at around 12 kg and the explosive force at around 1,800 tons of TNT . The cost of building a plant to produce 1 kg of 235 U per day was estimated at £ 5 million and it was determined that enormous human resources (large numbers of technicians and scientists) would be required for the enrichment process and construction. The effects of an atomic bomb explosion with long-lasting and extensive radioactive contamination of the environment have been described. The report concluded by stating that a German nuclear weapons project was possible and that activities aimed at building a high priority bomb should be promoted in cooperation with the US.
The second report, which dealt with the non-military use of atomic energy, found that nuclear fission had considerable potential on the one hand for energy generation and on the other for the production of radioisotopes that could be used for other purposes . The report mentioned the possible use of heavy water or graphite as a moderator for slowing down fast neutrons. It was recommended that more intensive research into the civil use of atomic energy be carried out only after the end of the war. The commission recommended that Hans von Halban and Lew Kowarski should move to the USA to take part in the activities for the production of heavy water. The possibility that plutonium might be more suitable than 235 U was mentioned and further research on it in the UK was recommended.

After the reports had been drawn up, the commission considered its task fulfilled and disbanded again.

Cooperation with the United States

The reports of the MAUD commission had been passed on to Lyman Briggs, the head of the American Advisory Committee on Uranium . However, there was no reaction from there to the report. When Marcus Oliphant finally flew to the United States in August 1941 to speak directly to Briggs, he found that Briggs had locked the reports in his safe and had not shown them to any of his colleagues. Oliphant then spoke directly to the other members of the Advisory Committee , including Samuel King Allison in Chicago, who was impressed by the haunting descriptions of the need to construct an atomic bomb to forestall Nazi Germany. Oliphant told Allison that building such a bomb would require such great resources of money and human capital that it could only be done in the United States under the terms of the war, not in Britain. In Chicago, Oliphant also visited Ernest Lawrence , James Bryant Conant and Enrico Fermi and explained to them the urgency of the project.

At first, nuclear research activities in the USA started hesitantly. Vannevar Bush , the chairman of the American National Defense Research Committee (NDRC) summoned Arthur Compton and the National Academy of Sciences to prepare a report on the possible uses of atomic energy. The report was published on May 17, 1941, but made no reference to the possible construction of a bomb. Not least because of the activities of Oliphant, the American Office of Scientific Research and Development (OSRD) was founded in December 1941 by Vannevar Bush , which had significantly expanded competencies and was able to tackle larger construction tasks in addition to research activities. The first step towards what would later become known as the Manhattan Project was thus taken.

Great Britain had also started its own nuclear weapons project under the code name Tube Alloys .

Interests of the Soviet Union

As early as autumn 1941, the NKVD received a copy of the report from the MAUD commission. As a result, the first activities with regard to research and construction of an atom bomb began in the Soviet Union .

See also

Individual evidence

  1. ^ Nekrasow, Wladimir F .: NKVD - MWD i atom, (The NKVD / MWD and the Atom), Moscow 2007

literature

  • Philip L. Cantelon, Richard G. Hewlett, Robert C. Williams (Eds.): The American Atom - A documentary history of nuclear policies from the discovery of fission to the present University of Pennsylvania Press, 2nd edition 1991, Philadelphia, PA , ISBN 0-8122-1354-8

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