A calutron is a mass spectrometer used for separating the isotopes of uranium. It was developed by Ernest O. Lawrence during the Manhattan Project and was similar to the cyclotron invented by Lawrence. Its name is a concatenation of Cal. U.-tron, in tribute to the University of California, Lawrence's institution and the contractor of the Los Alamos laboratory. They implemented industrial scale uranium enrichment at the Oak Ridge Y-12 plant established during the war and provided much of the uranium used for the "Little Boy" nuclear weapon, which was dropped on Hiroshima in 1945.
In a mass spectrometer, a vaporized sample is bombarded with high energy electrons, which cause the sample components to become positively charged ions. They are then accelerated and subsequently deflected by magnetic fields, ultimately colliding with a plate and producing a measurable electric current. Since the ions of the different isotopes have the same electric charge but different masses, the heavier isotopes are bent less by the magnetic field, causing the beam of particles to separate out into several beams by mass, striking the plate at different locations. The mass of the ions can be calculated according to the strength of the field and the charge of the ions. An ordinary mass spectrometer is designed to analyse the composition of very small samples; the calutron uses the same principle, but is designed to separate substantial quantities of known isotopes.
Initially a type of calutron known as Alpha was used; it enriched uranium to about 15% 235U. A later design, called Beta, further enriched the output of Alpha, optimising the initial design for the smaller quantities of already enriched feedstock.
Due to the wartime copper shortage the electromagnets were made using thousands of tons of silver borrowed from the U.S. Treasury. To take full advantage of the required large electromagnet, multiple calutrons were arranged around it in a large oval, called a race track because of its shape.
Calutrons use very substantial amounts of electrical power. It is estimated that calutrons built in Iraq by the Baath regime of Sadam Hussein required about 140 MW for 90 calutrons.
Magnetic separation was later abandoned in favor of the more complicated, but more effective, gaseous diffusion method.
Other articles related to "calutron, calutrons":
1942-1945 - Roman was manager of calutron uranium isotope separator design for the Manhattan Project under a contract with Westinghouse Electric. ... Groves funded design and construction of a gigantic array of calutrons for separation of uranium isotopes ... After preliminary calutron designs were tested at Berkeley using Lawrence's cyclotron, Westinghouse began manufacturing calutrons for installation at Oak Ridge, Tennessee, where the Y-12 plant ...
... The main Calutron patents are Methods of and apparatus for separating materials (Ernest O ... shims (Robert Oppenheimer and Stanley Frankel), and Calutron system (Ernest O ...
... Tarmiya was the site of the 20 calutrons used to enrich uranium to 35%, located in two buildings at the site ... “chemical wash” facility for recovering uranium from refurbished calutron components ... led to the positive identification of the Iraqi calutron program ...