Stanley Gerald Thompson (9.03.1912-16.07.1976) was an American nuclear chemist. He was born in Los Angeles. He graduated from the University of California, Los Angeles (1934). In 1934-42 he worked at the Standard Oil Company, and in 1942-46 at the Metallurgical Laboratory of the University of Chicago. From 1946 he worked at the E. Lawrence Radiation Laboratory of the University of California (Berkeley).
His research was in the fields of nuclear chemistry, nuclear spectroscopy, the alpha decay of heavy isotopes and spontaneous fission. He developed the process for separating plutonium-239. Together with others he discovered five superheavy elements (berkelium, californium, einsteinium, fermium, mendelevium) and 40 isotopes. He was one of the first to propose producing heavy elements in nuclear reactors.