Operation Big

Operation Big was a task force which was part of Operation Alsos the Allied. investigation of Nazi scientific developments (including the nuclear program) during the final days of World War II. Alsos was headed by Lt-Col Boris Pash with Dr Samuel Goudsmit as chief scientific advisor.

Worried that French forces might beat the US to Werner Heisenberg's laboratory in Hechingen, Pash hastily organized a flying column of Sixth Army combat engineers ("Task Force A"). His team reached Horb three days later and headed for Haigerloch while the French troops occupied themselves with looking for members of the Vichy Government in the nearby Sigmaringen enclave.

In April 1945, U.S. engineers dismantle the nuclear pile that German scientists had build up under the Uranprojekt program in Haigerloch.

Pash and his engineers, accompanied by General Eugene Harrison, the Sixth Army Group's Chief of Intelligence, overran Haigerloch on 23 April 1945. In a laboratory in a cellar they found a German experimental nuclear reactor whose vessel was empty of uranium and heavy water. A few drums of heavy water were later found in the laboratory's main chamber[1] and a German scientist told Pash that the reactor's uranium cubes had been concealed beneath hay in a nearby barn.

Pash subsequently had the empty reactor blown up. The task force then proceeded to Hechingen where they found and detained Erich Bagge, Carl Friedrich von Weizsäcker, Max von Laue, and Karl Wirtz, then went on to Tailfingen where they arrested Otto Hahn. Werner Heisenberg, who had left Hechingen on 19 April, was captured by Pash and a small force at his home in Urfeld am Walchensee, on 3 May 1945.[2]

Pash concluded that the German nuclear program had been years behind the Manhattan Project and that there was no possibility of them mounting any form of last-ditch nuclear attack. He called it "probably the most significant single piece of military intelligence developed during the war".[3]

Notes

  1. ↑ Dahl, Per F. (1999). Heavy Water and the Wartime Race for Nuclear Energy. CRC Press. p. 261. ISBN 0-7503-0633-5.
  2. ↑ Rotter, Andrew J. (2008). Hiroshima: The World's Bomb. Oxford University Press. p. 80. ISBN 0-19-280437-5.
  3. ↑ Cohen, Daniel (1999). The Manhattan Project. Twenty-First Century Books. p. 61. ISBN 0-7613-0359-6.