Franco Rasetti

Franco Rasetti

Franco Dino Rasetti (August 10, 1901 – December 5, 2001) was an Italian scientist. Together with Enrico Fermi, he discovered key processes leading to nuclear fission. Rasetti refused to work on the Manhattan Project, however, on moral grounds.

Rasetti was born in Castiglione del Lago, Italy. He earned a doctorate in physics at the University of Pisa in 1923, and Fermi invited him to join his research group at the University of Rome.

In 1928-1929 during a stay at the California Institute of Technology (Caltech), he carried out experiments on the Raman effect. He measured a spectrum of dinitrogen in 1929 which provided the first experimental evidence that the atomic nucleus is not composed of protons and electrons, as was incorrectly believed at the time.

In 1930, he was appointed to the chair in spectroscopy at the Sapienza University of Rome in the famous Physics Institute in Via Panisperna. His colleagues included Oscar D'Agostino, Emilio Segrè, Edoardo Amaldi, Ettore Majorana and Enrico Fermi, as well as the director Orso Mario Corbino. Rasetti remained in this post until 1938.

Rasetti was one of Fermi's main colloaborators in the study of neutrons and neutron-induced radioactivity. In 1934, he participated in the discovery of the artificial radioactivity of fluorine and aluminium which would be critical in the development of the atomic bomb.

In 1939 the advance of fascism and the deteriorating Italian political situation led him to leave Italy, following the example of his colleagues Fermi, Segré and Bruno Pontecorvo. With Fermi he had discovered the key to nuclear fission, but contrary to many of his colleagues, he refused for moral reasons to work on the Manhattan project.

From 1939 to 1947, he taught at Laval University in Quebec City (Canada), where he was founding chairman of the physics department.

In 1947, he moved to the United States where he became a naturalized citizen in 1952. Until 1967, he held a chair in physics at Johns Hopkins University in Baltimore.

After 1960, he was more and more interested in natural sciences. He became an expert on trilobite fossils and on wildflowers in the Alps. He died in Waremme, Belgium at the age of 100. The Nature obituary noted that Rasetti was one of the most prolific generalists whose work and writing are noted for the elegance, simplicity and beauty.