Maria Goeppert Mayer
1906–1972, Kattowitz, German Empire (now Katowice, Poland), San Diego, California, USA
German-American physicist who proposed the nuclear shell model explaining the stability of magic-number nuclei; second woman to win the Nobel Prize in Physics.
Trained at Göttingen under Max Born, Goeppert Mayer spent years in unpaid or peripheral posts because of anti-nepotism rules, at Johns Hopkins, Columbia and Chicago. At Argonne in the late 1940s, puzzling over the 'magic numbers' of neutrons and protons, she realized that a strong spin-orbit coupling closes nuclear shells — the insight that completed the shell model she developed in parallel with J. Hans D. Jensen.
Nobel-winning work
Goeppert Mayer shared the 1963 Nobel Prize for discoveries concerning nuclear shell structure. Nuclei with certain 'magic' numbers of protons or neutrons (2, 8, 20, 28, 50, 82, 126) are exceptionally stable, but the independent-particle picture could not reproduce them until her 1948–1949 proposal.
She postulated that each nucleon moves in a mean potential with a strong spin-orbit term that splits the levels; the resulting shells close exactly at the magic numbers, explaining spins, parities and isomerism. The shell model remains the foundation of nuclear structure theory.
Workplaces: Argonne National Laboratory, University of California, San Diego
United States, Germany