John Douglas Cockcroft (27.05.1897—18.09.1967) was an English physicist and a Fellow of the Royal Society (1936). He was born in Todmorden. He studied at the University of Manchester and graduated from the University of Cambridge (1924). From 1925 he worked at the Cavendish Laboratory under E. Rutherford, from 1934 he headed the Mond Laboratory of the Royal Society, and at the same time he taught (1929—46) at the University of Cambridge (professor from 1939). In 1946 — 59 he headed the atomic research centre at Harwell, and in 1959 — 65 he was head of Churchill College in Cambridge.
His research concerned nuclear physics, accelerator technology, nuclear power and the problem of thermonuclear fusion. His first studies were on the production of strong magnetic fields and the attainment of low temperatures. In 1928 he took up the problem of accelerating protons, and in 1932, together with E. Walton, he constructed a high-voltage apparatus, the cascade generator (the Cockcroft — Walton generator), on which in April 1932 he carried out the first nuclear reaction with artificially accelerated protons — the transmutation of lithium. In the following year they studied a number of cases of the transmutation of elements brought about by accelerated protons (Nobel Prize, 1951). He proved experimentally that nuclear fusion reactions of light elements are possible under the action of accelerated protons and deuterons. He was one of the inventors of English radar. He did much for the development of nuclear power and for the launching of thermonuclear research in England.
An honorary member of a number of academies of sciences, scientific institutions and societies. The D. Hughes (1938), M. Faraday (1955), W. Kelvin (1956) and N. Bohr (1958) Medals, and the Atoms for Peace Award (1961).