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Goeppert Mayer, Maria,

nuclei atomic ‘magic shell

née Goeppert [goe pert may er] (1906–72) German–US mathematical physicist; discovered and explained the ‘magic numbers’ of nucleons in some atomic nuclei.

Maria Goeppert succeeded in making major contributions to science despite many obstacles. She first studied mathematics at Göttingen, perhaps because was a family friend, but in 1927, attracted by lectures, she switched to physics. She worked on electronic spectra and in 1930 married an American chemist, Joseph Mayer (1904– ). They went to Johns Hopkins where she had a lowly job with ‘one of the only two people there who would work with a woman’ – her husband. Her work on molecular spectra by quantum methods gained the respect of who invited the couple to Columbia, but they could find a paid job only for ‘Joe’. However, Maria continued to research, especially on the newly discovered elements heavier than uranium; so when the Second World War began and the atom bomb project developed, she was much in demand and soon led a team of 15 people. It was she who calculated the properties of UF 6 , the basis of a separation method for the ‘fission isotope,’ uranium-235.

After the war both Mayers went to Chicago and it was there in 1948 that Maria found the pattern of ‘magic numbers’: atomic nuclei with 2, 8, 20, 28, 50, 82 or 126 neutrons or protons are particularly stable. (The seven include helium, oxygen, calcium and tin.) This had first been noted by in 1933. At first Mayer offered no theory to account for this, although she saw the analogy with electron shell structures. However, by 1950 and aided by a clue from her friend Fermi, Mayer worked out (in ten minutes!) a complete shell model for atomic nuclei, in which spin orbit coupling predicted precisely the ‘magic number’ stable nuclei actually observed. In this model, the magic numbers describe nuclei in which certain key nucleon shells are complete. For this work she shared a Nobel Prize in 1963 with J H D Jensen (1907–73) of Heidelberg, who had arrived independently at rather similar conclusions on nuclear shell structure.

Goff, Eugenia Wheeler (1844–?) - Historical Geography [next] [back] Goebel, Dorothy Burne (1898–1976) - U.S. History

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