In 1976 Soviet scientists at the Joint Institute for Nuclear Research in Dubna, Russia, U.S.S.R., announced that they had synthesized element 107, later given the official name bohrium, by bombarding a target of bismuth-209 with ions of chromium-54. The resultant collisions were reported to have produced an isotope of the element with a mass number of 261 and a half-life of 1–2 milliseconds. The existence of the element was confirmed by West German physicists at the Institute for Heavy Ion Research (Gesellschaft für Schwerionenforschung 【GSI】) in Darmstadt.