50 years GSI



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Roentgenium - 16 years ago element 111 was discovered



On December 8, 1994 an international research team led by Professor Sigurd Hofmann deteced exactly 16 years ago, element 111 for the first time. At that time a total of three atoms of the new element could be observed in the experiment at the accelerator facility at GSI. In later experiments at GSI and the japanese accelerator facility RIKEN more atoms of element 111 were detected, which confirmed the discovery beyond doubt.

Roentgenium, 272 times heavier than hydrogen, was created through nuclear fusion by bombarding a bismuth film with nickel ions. The element decays after a split second and can only be detected with very sensitive methods of analysis.
Its name honors the physicist and the first Nobel Prize winner Wilhelm Conrad Röntgen (1845-1923). Learn more: German Press Release Naming Ceremony and YouTube video: Rg - The Periodic Table of Videos

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