Arthur Compton (Compton)

September 10, 1892, Mr.. - March 15, 1962
American physicist Arthur Holly Compton was born in Worcester (Ohio). His parents were Elias Compton, a Presbyterian minister, professor of philosophy and dean of Worcester College, and Katherine Hotels (Ogspurger) Compton. Developing in the atmosphere of a cultured family, Arthur soon showed an interest in the natural sciences, collecting butterflies and studying paleontology and reading books on astronomy. After Worcester College in 1913. with a bachelor's degree, he became a graduate student, a physicist at Princeton University and received a master's degree in 1914. Two years later he became a doctor, writing a dissertation on the interaction of X-rays with matter.
To. spent a year teaching physics at the University of Minnesota and then served two years as an engineer-researcher in Pittsburgh in the 'Westinghouse Lamp Company'. Here he has been developing and designing the lamp containing sodium vapor, and after the United States entered the First World War, helped to create aircraft instruments for Army Signal. While working in the company "Westinghouse" he continued to study X-rays, which subsequently led to his discovery of the effect named after him.
Fascinated by pure science, K. in 1919. received a scholarship from the National Research Council and spent a year at the Cavendish Laboratory at Cambridge University. It was an exciting time: K. witnessed the first experiments by Ernest Rutherford splitting the atom, which he later called the decisive factor in his academic life. Because the Cavendish Laboratory was not a high-voltage X-ray machine, K. studied the scattering and absorption of gamma rays, which constitute the high-energy X-rays emitted by radioactive nuclei. He noticed that the scattered radiation is easily absorbed by the substance than the primary radiation (radiation that bombarded the target), but neither he nor his colleagues at Cambridge could not explain this phenomenon using the laws of classical physics.
. During the first two decades of XX century
. physics is gradually coming to realize that classical physics can not explain the events occurring at the atomic or intra-level. Max Planck, Albert Einstein, Niels Bohr and others have developed a new theory to explain some of sub-atomic phenomena, based on the radical assumption that energy is quantized, ie. that energy can be transferred only discrete portions, or quanta. Quantum theory has proved very useful for explaining the previously seemed mysterious phenomena, and it allowed Bohr to construct the most convincing of all the proposed models of the atom. However, in its original form of quantum theory could not cope with the analysis of more general problems, and most physicists were not convinced of its fundamental importance. Between 1910 and 1920. K. with other physicists, who studied the interaction of matter and energy, continued to look for the classic explanation of their experimental results.
Back in 1920,. in the United States, to. headed the Department of Physics at Washington University in St. Louis (Missouri), where he performed his most famous experiments. With the help of X-ray spectrometer U.G. Bragg, he made accurate measurements of the wavelength of X-rays scattered at the target. K. found that the scattered radiation is of two sorts: one wavelength coincides with the wavelength of primary radiation, and the other has a longer wavelength. The increase in wavelength, which became known as the Compton effect was proportional to the angle of scattering. Again, the results of K. did not yield an explanation in terms of classical physics, but this time he made a decisive step, turning to the quantum theory. He found that the increase in wavelength can be explained by considering the X-rays as particles with values of energy and momentum predicted by quantum theory. X-ray beam - 'particle energy', . or quantum, . - Soudaryayas with the electron target, . electron gives part of its energy and therefore, . after the collision the particle has less energy, . which corresponds to a lower frequency - or more wavelength - radiation,
. Rediscovery By. agreed with his earlier discovery, . where it was a matter, . the scattered gamma rays are easily absorbed by the substance, . than the primary gamma-rays and low-energy (longer-wavelength) radiation is easily absorbed, . than the high-energy (with a shorter wavelength).,
. As the light, like X-rays, is a form of electromagnetic radiation, the Compton effect was a strong argument in support of the nominated in 1905
. Einstein's assumption that light has properties not only waves but also the particle. The particle properties of electromagnetic radiation manifested in the interaction of primary X-rays and electrons, . whereas the wave properties were observed when detecting the scattered rays - Effects of the spectrometer can be explained, . just looking at X-rays as waves.,
. K
. published his results in 1923, and in the same year he became a professor at the University of Chicago. He speculated that the scattering of X-rays, electrons, which happened this scattering, emitted from atoms with high speed. Such recoil electrons as they are called K, have been discovered and experimentally verified later in the year CH.T.R. Wilson, whose invention of the condensing chamber allowed to observe the tracks of electrically charged particles.
Results By. caused a stir among physicists, but its quantum interpretation was not accepted immediately, because it contradicted the ideas Dzh.Dzh. Thompson. American physicist William Doohan opposed to the theory. and tried to show that these K. could be associated with other effects. K., Doohan and other physicists have carried out additional experiments, and in 1924. Doohan withdrew their objections, convinced that his own measurements perfectly consistent with the theory to. Recognition of the Compton effect has been an important stimulus for the development of quantum mechanics, a complex mathematical interpretation of quantum theory with deep and far-reaching applications in physics and chemistry.
In the 20-ies. K. held other important studies of X-rays. For example, in 1922. it showed that X-rays are totally reflected from smooth surfaces such as glass or metal, thereby demonstrating that X-rays behave like light. In 1925, Mr.. K. together with his colleagues received this effect by using a diffraction grating spectrometer, which allowed to divide the scattered X-rays on the components with the corresponding wavelengths. Their work laid the foundations for the study of X-rays as a branch of optics, and this alone would have to. reputation as an outstanding scientist.
To. received in 1927. Nobel Prize in Physics "for his discovery of the effect named after him '. He shared the award with CH.T.R. Wilson. Introducing the winners, . Kai Siegbahn of the Royal Swedish Academy of Sciences noted, . that the Compton effect 'is now so important, . that in future none of the atomic theory can not be accepted, . if she does not agree with him and not follow the laws, . established by its discoverer. ",
. After receiving the prize to
. engaged in developing ways of experimental research on the distribution of electrons in atoms. Together with the measurement of energy X-rays Kai Sigbanom this work formed the basis for subsequent theories of atomic structure. Experimental studies of K. also made contributions to understanding the magnetic properties of ferromagnetic materials such as iron.
In the early 30-ies. K. interested in cosmic rays (radiation incident on the earth from outer space), because the interaction of gamma rays and electrons in cosmic rays provides an important example of the Compton effect. Between 1931 and 1933. He led expeditions to many parts of the world to obtain data on cosmic rays. Based on this information, he confirmed date back to the 20-ies. Jacob Clay's conclusions about the changing intensity of cosmic rays, depending on the latitude. K. correctly explained the change by showing that, contrary to the prevailing opinion of the cosmic rays influenced Earth's magnetic field and are, at least in part, of charged particles.
In 1941, Mr.. K. headed the Department of Physics and became the dean of the Division of Physical Sciences, University of Chicago. In the same year he led a committee of the National Academy of Sciences, created to study the possible use of atomic energy for military purposes. Favorable opinion of this group led to the approval of the Manhattan Project. From 1942 to 1945. K. was the director of one of the units of the project, known as the Metallurgical Laboratory of the University of Chicago. Here, under the leadership of Enrico Fermi built the first nuclear reactor. Later. supervised the construction of Oak Ridge National Laboratory in Tennessee, which had to deal with the separation of uranium-235 from the more common uranium-238.
When K. offered in 1945. to lead the University of Washington, he decided to accept the offer and leave Chicago, even though the new post and meant for him the end of research. After retiring from his post as head of the university in 1954, he remained an honorary professor of physics at Washington University. From this post he left in 1961, assuming divide his time between Washington University, Worcester College and the University of California at Berkeley.
In 1916, Mr.. K. married Betty Charity Mc Kloski, they had two sons. All his life his wife was his loyal assistant in the work, and during the Second World War, at his insistence, she even got access to the secret work along with him. The man is bright and outstanding, K. was able to kindle enthusiasm in his pupils and associates. Sincerely religious, he headed Leymenskoe missionary movement from 1934 to 1948. and actively participated in the National Conference of Christians and Jews. He died of a brain haemorrhage 15 March 1962, Mr.. Berkeley (California).
Among the numerous awards to. You can specify the Rumford Medal of the American Academy of Arts and Sciences (1927), . Hughes Medal of the Royal Society of London (1940), . Franklinovskogo Medal of the Franklin Institute (1940) and the Medal of Merit of the Government of the United States (1946),
. He received honorary degrees from many universities, including Yale, Princeton and Harvard. K. was a member of the American Association for the Advancement of Science, the American Philosophical Society, the American Physical Society, the National Academy of Sciences of the USA and the New York Academy of Sciences and a member of more than 20 foreign scientific societies.
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