Otto Hahn
Otto Hahn was the chemist whose discovery of nuclear
fission ultimately led to the ending of
WW II by the terrible drop of atomic bombs on
Hiroshima and Nagasaki in August 1945.
The story of Hahn's discovery began
in 1938 with a report by Irène Joliot-Curie that
bombarding uranium with neutrons had resulted
in the production of a radionuclide of thorium,
which they later speculated was a transuranium
element similar to lanthanum. The astounded
Hahn told Irène's husband, Frédéric, that such
a thing was nonsense and that he would
perform an experiment to prove as much. In the
process of duplicating her work, Hahn and
co-worker Fritz Strassmann discovered that,
among other things, three isotopes of barium had
been produced. This was incredible because the
mass of barium is about half that of uranium.
No known reaction could explain such a huge change.
When they published their results (Jan. 6,
1939) Hahn and Strassmann noted that such a thing was
"in opposition to all the phenomena
observed up to the present in nuclear physics." Hahn,
conscious of the fact that as a chemist he
was trading in the domain of physics, did not offer
an explanation. Instead, he left it up to Lise
Meitner, his longtime collaborator, to whom he had
sent a letter (December 19, 1938)
describing his findings and asking "Perhaps you can
suggest some fantastic explanation,"
which she explained as nuclear fission. Nevertheless,
despite the contributions of Strassmann
and Meitner, it was Hahn who was awarded
the 1944 Nobel Prize in chemistry for the
discovery. Unfortunately, Hahn was not at the
awards ceremony to receive his prize. At the
time he learned of the award, he was being held
by the British who were seeking information
from him about the failed German effort to develop
an atomic bomb. As the Chairman of the
Nobel Committee for Chemistry reported
"Professor Hahn . . . has informed us that he is
regrettably unable to attend this ceremony."
Created June 9, 2002 by
Andreas Aste.
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