Aage Bohr : biography
Aage Niels Bohr ( 19 June 1922 – 9 September 2009) ("Nobel Prize winner Aage Bohr has died"), politiken.dk, 10 September 2009 was a Danish nuclear physicist and Nobel laureate, and the son of the famous physicist and Nobel laureate Niels Bohr.
Life and career
Bohr was born in Copenhagen in 1922, and grew up surrounded by physicists such as Wolfgang Pauli and Werner Heisenberg, who were working with his father at the Institute for Theoretical Physics (now the Niels Bohr Institute) at the University of Copenhagen.
In 1940, shortly after the German occupation of Denmark, Bohr began his physics degree at the University of Copenhagen. In October 1943, shortly before he was to be arrested by the German police, Niels Bohr escaped to Sweden with his family, later travelling to London and on to work on the Manhattan Project. During this time, Aage Bohr travelled with his father, acting as his assistant and secretary.
The Bohrs returned to Denmark in 1945, and Aage resumed his university education, graduating with a master’s degree in 1946, with a thesis concerned with some aspects of atomic stopping problems. Following graduation, he became an associate at the Niels Bohr Institute.
Bohr worked at the Institute for Advanced Study in Princeton in early 1948, and later at Columbia University from January 1949 to August 1950. While in the US, Bohr married Marietta Soffer; the couple had three children, Vilhelm, Tomas and Margrethe.
Only after doing his Nobel Prize-winning research did Bohr receive his doctorate from the University of Copenhagen, in 1954 or 1956. Bohr became a professor at the University of Copenhagen in 1956, and, following his father’s death in 1962, succeeded him as director of the Niels Bohr Institute, a position he held until 1970. He was also a member of the board of the Nordic Institute for Theoretical Physics (Nordita) from its inception in 1957, becoming its director in 1975. In 1978 he was elected to the Pontifical Academy of Sciences.
Aage Bohr’s son, Tomas Bohr, is a Professor of Physics at the Technical University of Denmark, working in the area of fluid dynamics. Tomas’s two cousins, Jakob and Henrik Bohr, are also professors at the Technical University of Denmark. Jakob at DTU Nanotech, and Henrik also in the Physics Institute and Director of the Quantum Protein (QuP) Center.
By the late 1940s it was known that the properties of atomic nucleus could not be explained by the then-current models (such as the liquid drop model developed by Niels Bohr amongst others). The shell model, developed in 1949, allowed some additional features to be explained, in particular the so-called magic numbers. However, there were also properties which could not be explained, including the non-spherical distribution of charge in certain nuclei.
James Rainwater of Columbia University suggested a model of the nucleus which could explain a non-spherical charge distribution in a 1950 paper. Bohr, visiting Columbia at the time, had independently conceived the same idea, and submitted a paper for publication about a month after Rainwater’s which discussed the same problem along more general lines. Bohr later developed the idea further, in 1951 publishing a paper which comprehensively treated the relationship between oscillations of the surface of the nucleus and the movement of the individual nucleons.
On his return to Copenhagen in 1950, Bohr began working with Ben Roy Mottelson to compare the theoretical work with experimental data. In three papers which were published in 1952–53, Bohr and Mottelson demonstrated close agreement between theory and experiment; for example, showing that the energy levels of certain nuclei could be described by a rotation spectrum. This work stimulated new theoretical and experimental studies. As a result, he won the Atoms for Peace Award in 1969.
Bohr, Mottelson and Rainwater were jointly awarded the 1975 Nobel Prize in Physics "for the discovery of the connection between collective motion and particle motion in atomic nuclei and the development of the theory of the structure of the atomic nucleus based on this connection".
Bohr and Mottelson continued to work together, publishing a two-volume monograph, Nuclear Structure. The first volume, Single-Particle Motion, appeared in 1969, and the second volume, Nuclear Deformations, in 1975.