HILAC

In 1967 the scientists of the Joint Institute of Nuclear Research in Dubna, Russia, bombarded americium-243 with neon-22 to produce two isotopes of unnilpentium, then known as hahnium. The reaction is as follows jAm-243 + Ne-22 —> jjjjHahnium-260 and 261 (Unp-260 and 261). In 1970 Albert Ghiorso and his team at Berkeley bombarded califor-nium-249 with heavy nitrogen (N-15) in their Heavy Ion Linear Accelerator (HILAC). The reaction is as follows gCf-249 + -15 —> j jHa-260 (Unp-260). 

Alternative scenarios, such as might be devised from transfer-product decays or random events, were found to be unlikely by orders of magnitude and, on balance, the association of this event with the formation of element 110 appears to be the simplest and most probable explanation of the observation. Unfortunately, the Super-HILAC has been shut down so that it is impossible to repeat the experiment in the very near future. 

The Super HILAC Accelerator at the University of California, Berkeley... 

The bombardment was effected in the new Hilac, or heavy ion linear accelerator, in Berkeley. A linear accelerator, as the name implies, accelerates particles along a straightaway rather than around a circular course as in the cyclotron or bevatron. 

Accelerators designed specifically for the purpose of producing such heavy ions are being built at several laboratories. Berkeley s "Hilac, which can bombard targets with particles as heavy as neon ions, or even heavier ones, is just one example. 

Such machines naturally call for vacuum tanks of considerable size, as this interior view of the Hilac illustrates. The vacuum tank encloses the course along which the bombarding particles are accelerated. 

Heavy Ion Linear Accelerator (Super HILAC) as a source of heavy ions to bombard a 259- ig target of This resulted in the production and positive identification of 106, which decayed with a half-life of 0.9 0.2 s by the emission of alpha particles as follows ... 

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