McMILLAN (McMillan), Edwin M.( The American physicist, Nobel Prize in Chemistry, 1951)
Comments for McMILLAN (McMillan), Edwin M.
Biography McMILLAN (McMillan), Edwin M.
genus. September 18, 1907
American physicist Edwin Mattison McMillan was born in Redondo Beach (California), a family physician Edwin Harbaugh McMillan and Anna Mary (Mattison), McMillan. The family soon moved to Pasadena, where M. received his primary and secondary education. Being engaged in high school in Pasadena, he attended a public lecture at Caltech, where he later majored in physics, received in 1928. Bachelor's degree, and the following year became Master of Science. Doctoral degree he was awarded in 1932. Princeton University for a thesis on the molecular beams. After that, he worked at the University of California at Berkeley as a fellow of the State Research Foundation. When in 1934. Ernest O. Lawrence founded the Lawrence Radiation Laboratory in Berkeley, M. became one of its employees. During the years of work in the laboratory, he made a significant contribution to improving the technology of the cyclotron, as well as in nuclear physics and chemistry.
. Lawrence invented the cyclotron is a particle accelerator, protons and telling nuclei of atoms are very high energy
. In a cyclotron, more compact than linear accelerators, the magnetic field is used to make the particles move in a curved path. Charged particles placed in the center of the chamber, are accelerated by using an alternating electric field having a frequency which coincides with the frequency of circulation of these particles in their orbits. With the increasing speed of the particles increases and the diameter of their orbit, during the same treatment remains constant. Fluctuations of the electric field gradually dispersed particles moving in a spiral to the message they are very high energy.
. In 1938, trying to create new chemical elements through the introduction of neutrons in the nucleus of uranium, German chemists Otto Hahn and Fritz Strassmann and Lise Meitner were instead splitting (fission) of uranium nuclei
. M. held at the cyclotron at Lawrence Radiation Laboratory similar experiments to study the effect of neutrons on uranium. In 1940. He and his fellow Philip Abelson found that some of the nuclei of uranium atoms when bombarded with neutrons are not subjected to cleavage. Instead, they, as predicted six years earlier, Enrico Fermi, disintegrated, forming a new element, whose atomic nucleus containing 93 protons and electrons. This element, named neptunium on behalf of the planet Neptune, was the first synthesized transuranic (heavier than uranium) element. The study, begun Moscow, continued Glenn T. Seaborg and his colleagues, who in 1941. discovered plutonium.
. In the Second World War, M., . fulfilling military orders, . engaged sonar, . microwave radar installations (radar), and nuclear weapons, . working in Berkeley, . the Massachusetts Institute of Technology (1940 ... 1941), . in the laboratory of radio and voice communications naval forces in the U.S. San Diego (1941 ... 1942) and on the implementation of the Manhattan Project at Los Alamos (1942 ... 1945),
. After the war he received the position of professor of physics at the University of California at Berkeley, and in 1954. became deputy director of the Lawrence Radiation Laboratory. Since 1958. to the resignation in 1973. he headed the laboratory, which since 1971. became known as the Lawrence Berkeley Laboratory.
In 1945, Mr.. M. addressed the problem concerning the cyclotron. The orbital period of particles in a cyclotron is constant only if the mass of the particle remains constant. In accordance with the theory of relativity, Albert Einstein, when the speed of the moving body approaches the speed of light, body weight increases. This implies that the kinetic energy of the body can reach very high levels without significantly increasing its speed, since most of the energy goes to increase body weight. However, as the mass of the orbiting particle increases, it takes more time to complete traffic. Thus, the rhythm ceases to coincide with the rhythm of oscillatory electrical impulses in the cyclotron. Proposed M. The solution lies in changing the magnetic field strength or frequency of electrical impulses so, . to conform to the decreasing rate of orbiting particles, . which is made to move in a circle with constant radius, . not a spiral, . in cyclotron,
. (M. did not know - because the Soviet scientific journals are not distributed in the United States during the Second World War - that a year earlier, the Russian physicist Vladimir and. Wexler put forward exactly the same concept.) Energy, . which can be achieved in such accelerators, . called synchrotron, . limited only by the diameter of the accelerator and the strength of the magnetic field, . created for, . to keep their energy inside the particle.,
. In 1951, Mr.
. M. with Seaborg was awarded the Nobel Prize in Chemistry "for his discoveries in the chemistry of transuranic elements'. In his opening speech on behalf of the Royal Swedish Academy of Sciences п-.пг. Vestgren welcomed M. as a scientist who established the existence of transuranic elements: 'You were the first who succeeded in this case. His achievements you have opened a field of research, in which occur large, are fundamental to science and technology achievements. His later work on the problem of the accelerator you will also actively contribute to further progress in this field of chemistry '.
After receiving the Nobel Prize M. continued to be actively engaged in research activities until his retirement from the University of California at Berkeley in 1973
In 1941, Mr.. M. married Elsie Blumer, daughter of the dean of the Yale Medical School. In the couple a daughter and two sons.
In addition to the Nobel Prize, M. won awards for scientific achievements of the American Research Corporation (1951) and 'Over the peaceful atom' Fund 'Ford Motor Company' (1963). Scientist - a member of the U.S. National Academy of Sciences, the American Physical Society, the American Academy of Arts and Sciences and the American Philosophical Society. It consists of many organizations, . involved in politics in science and physics of high energy, . including the Atomic Energy Commission U.S., . 'Rand Corporation', . International Union of Pure and Applied Physics and Stanford Linear Accelerator Center.,