BOR (Bohr), Aage( Danish physicist, Nobel Prize in Physics, 1975)
Comments for BOR (Bohr), Aage
Biography BOR (Bohr), Aage
born June 19, 1922
Danish physicist Aage Niels Bohr was born in Copenhagen and was the fourth of six sons of Margaret (nee Norlund), Niels Bohr and Bohr. Growing up in the atmosphere of the Institute of Theoretical Physics (now the Niels Bohr Institute) in Copenhagen, who led his father, the boy met many leading physicists world-famous. After graduating high school in Sortsdame, he began to study physics at the University of Copenhagen in 1940, in the same year, when Germany occupied Denmark. Order to avoid imminent arrest by the Gestapo service, Niels Bohr in 1943. fled to Sweden, where he was joined by all other members of the family. Then Aage accompanied his father to England and then in the U.S., where the elder Bohr played a leading role in the Manhattan Project to build atomic bomb. Los Alamos Scientific Laboratory (New Mexico) B. was for his father's secretary and assistant in all his affairs.
When World War II ended, the family Bohr returned to Denmark. After receiving a master's degree at the University of Copenhagen in 1946, B. he became an assistant researcher at the Institute for Theoretical Physics. He returned to the United States in 1949. to work at the Institute for Basic Research in Princeton (New Jersey), as well as to conduct research at Columbia University. At Columbia University, IA. Rabi arouse B. interest in the hyperfine structure of deuterium, in particular to the splitting of the lines of its atomic spectrum, and B. remained here until 1950 to complete the theoretical study. All this time he worked in the same room with James Rainwater, with whom he discussed the fundamental questions concerning the structure of the atomic nucleus.
B. and Rainwater were not satisfied with the two previous models of the atomic nucleus. One of them, the droplet model, was launched in 1936. Father B. It was assumed that the protons and neutrons (collectively called - nucleons) are held together by nuclear forces in much the same way as water molecules are held in a drop of rain. Trickle theory gave a satisfactory explanation for such phenomena as nuclear fission, but she could not explain some other properties of the nucleus and especially the spectrum of excited states.
Another model was proposed by Maria Goeppert-Mayer, and I. Hans D. Jensen. Named the shell model, it describes the motion of the nucleons to the independent concentric orbits, or shells, inside the nucleus, similar to electron shells in atoms. According to the shell model, namely the sum of all the forces caused by nucleons, determines the behavior of each individual nucleon. The result is a so-called force field, which is believed Goeppert-Mayer and Jensen, has a spherical shape. The validity of this model is in doubt due to the fact that, as shown by experiment, the distribution of electrical charges surrounding the nucleus, some are not spherical.
After listening to a lecture by Charles X. Townes in 1949, Rainwater realized that the orbit can be distorted by centrifugal force. Similar ideas have come to BA, therefore on his return to Copenhagen in 1950, Mr.. B. and Benjamin P. Mottelson started working together, trying to give a new description of nuclear matter. Taking the submission Rainwater, they created a synthetic model that combines the properties of liquid core to its shell structure. This model is called the collective model.
. In the collective model of the surface of the nucleus behaves like the surface of a liquid drop, but the shell structure subjected to deformation, which appear on the surface in the form of vibrations and rotation
. If the outer shell is filled with nucleons, say B. and Mottelson, the nucleus has a spherical shape, if the outer shell is not filled until the end, the shape of the nucleus becomes distorted and melon-shaped. In such a deformed nucleus, they argue, there will be new modes of vibration and rotation, including surface waves and fluctuations in the size of the nucleus.
Collective model allowed B. and Mottelson not only to calculate the likely properties of deformed nuclei, but also to confirm the hypothesis of Rainwater. Their findings, they reported in 1953. The following year, B. received his doctorate from the University of Copenhagen, and in 1956. it took the post of professor of physics.
After the death of his father in 1962. B. was appointed director of the Institute of Theoretical Physics, in this post he remained until 1970 when, after retirement began a new period of active research. He became director of the Nordic Institute for Theoretical Atomic Physics (Nordita) in 1975. B., Mottelson and James Rainwater divided in 1975. Nobel Prize in Physics "for his discovery of the relationship between collective motion and the motion of individual particles in the atomic nucleus and the development of the theory of the structure of atomic nuclei, based on this relationship '. In his Nobel lecture B. called his work with Mottelson 'an important testing ground for many of the ideas of nuclear dynamics'. The response to these ideas, he said, 'played an important role in the development of dynamic concepts, ranging from celestial mechanics to the spectra of elementary particles'
After receiving the Nobel Prize, B. continued theoretical research in Nordita until his resignation in 1981. He married Marietta Bettina Soffer in 1950, they have two sons and a daughter. Three years after the death of his first wife in 1978. He married Bente Meyer. He likes listening to classical music. Advocated international cooperation of research, calling it a 'vital factor in the development of science itself', and 'a means of strengthening mutual knowledge and understanding among peoples. "
Among other awards B. be called Danny Heineman Prize of the American Physical Society (1960), . Award 'for the peaceful atom', . established by the Ford Foundation (1969), . Rutherford Medal of the London Physical Institute (1972) and Medal of John Price Uizerilla Franklinovskogo Institute (1974),
. He has an honorary degree from University of Oslo, Heidelberg, Trondheim, Manchester and Uppsala. He is a member of the Academies of Sciences of Denmark, Norway, Sweden, Poland, Finland and Yugoslavia, as well as a member of the U.S. National Academy of Sciences. American Academy of Arts and Sciences, American Philosophical Society and other professional societies.