Discovery of dubnium

Dubnium is a synthetic element with atomic number 105. A team at the Lawrence Berkeley Laboratory led by Albert Ghiorso reported making it in 1970 by bombarding californium-249 with nitrogen-15 nuclei, while Soviet researchers at Dubna had announced results from their own experiments about two years earlier. The dispute over priority was one of the so-called Transfermium Wars. In 1997 the international chemical authorities settled the matter by naming the element dubnium, after the Russian town of Dubna, where the Joint Institute for Nuclear Research is based, while names proposed by the Berkeley team were used for the neighbouring elements 104 and 106. Dubnium is radioactive, and its isotopes last for seconds at most, so only a few atoms have ever been studied.

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