The search for the heavy nuclei stability zone

The author presents the saga of the creation of heavy isotopes. Since the beginning in 1940 with the discovery of the neptunium to 1999 with the element 118, 23 new elements have been discovered. After having developed a very sensible method to identify nuclei obtained in fusion reactions of heavy ions, a Darmstadt team discovered the elements 107 to 112 between 1980 and 1996. Since 1996, European, American and Russian teams discovered 6 new elements to 118. As soon as 1966 a stability zone centered on the element 114 was predicted by theory. The synthesis of the element 114 is important because it is the experimental proof of the existence of this stability zone, the half-life of the element 112 is 240 microseconds whereas that of element 114 (with 175 neutrons) is about 30 seconds. (A.C.)