Glen Seaborg: We were searching for element 94 and on December 14th, 1940, we made our initial
bombardment of uranium oxide plastered onto a grooved copper plate using the 60-inch
cyclotron at Berkeley. Our plan was to search for an isotope of element 94 with a
relatively short half-life, one that would produce a more rapid emission of alpha
particles. We used a 16 MeV beam of deuterons from the cyclotron, hoping to find a
detectable source of alpha particles to prove the existence of element 94. We put
the material through a chemical procedure that would isolate element 93, hoping this
would decay to element 94. We did find radioactivity that decayed to an isotope that
emitted alpha particles, apparently an isotope of element 94. Ultimately the isolation
of element 94 required the chemical separation of the new element from all others,
and Arthur Wahl achieved that goal in February 1941. In March, Kennedy, Wahl, and
myself, working with Emilio Segre, created and identified the fissionable isotope
Plutonium-239. It soon became evident that this highly fissionable element, in addition
to its uses as a nuclear explosive and a nuclear fuel source, would also be valuable
in future trans-uranium research.
Clip
Creator: Glenn T. Seaborg Associated: Arthur C. Wahl, J.W. Kennedy, Emilio Segrè Clip ID: energy1167-element94
Full Work
Creator: Atomic Energy Commission Associated: Otto Hahn, Otto Frisch, Herbert Anderson, Glenn T. Seaborg, Chet Huntley
