Jean Thibaud (12.05.1901-21.05.1960) was a French physicist. He was born in Lyon. He graduated from the Higher School of Electrical Engineering in Paris (1925). He was an assistant to M. de Broglie, then professor at the University of Lyon (from 1935), in 1941—45 director of the School of Physics and Chemistry (Paris), and from 1953 of the Institute of Nuclear Physics in Lyon.
His research concerned atomic and nuclear physics (X-ray spectrography, α-, β- and γ-radioactivity, nuclear reactions, the fission of uranium). He established experimentally (1933) the annihilation of electrons and positrons in the bombardment of platinum by positrons. Independently of others he put forward in 1929 the idea of the cyclotron.