Otto
Hahn, the son of a glazier, was born in Frankfurt am Main, Germany,
on 8th March, 1879. He studied chemistry at the University of Marburg
and obtained his doctorate in 1901. Afterwards he became a lecturer
at the university.
In
1904 he went to London to study at University
College where he carried out research into radioactivity. He later
moved to Montreal where he worked under Ernest
Rutherford.
Rutherford
returned to Germany in 1906 where he began
work with Lise Meitner at the Kaiser
Wilhelm Institute for Chemistry. Hahn now became head of the radiochemistry
department.
On
the outbreak of the First World War Hahn was
recruited into the German Army. His
scientific knowledge was acknowledged and he became a chemical-warfare
specialist and organized the use of Chlorine
Gas and Mustard Gas against British
and French troops.
After
the war Hahn resumed working with Lise
Meitner and together they discovered
protactinium (1918) and nuclear isomers (1921). Over the next few
years they devoted their time to researching the application of
radioactive methods to chemical problems.
In
the 1930s Hahn became interested in the research being carried out
by Enrico Fermi and Emilio
Segre at the University of Rome. This included experiments where
elements such as uranium were bombarded with neutrons. By 1935 the
two men had discovered slow neutrons, which have properties important
to the operation of nuclear reactors.
Hahn
and Lise Meitner were
now joined by Fritz Strassmann and
discovered that uranium nuclei split when bombarded with neutrons.
In 1938 Meitner, like other Jews in Germany,
was dismissed from her university post. She moved to Sweden and
in 1939 wrote a paper on nuclear fission with her nephew, Otto
Frisch, where they argued that by splitting the atom it was
possible to use a few pounds of uranium to create the explosive
and destructive power of many thousands of pounds of dynamite.
During
the Second World War Hahn and Fritz
Strassmann continued
to work in the field of nuclear physics but they made no attempt
to turn their knowledge into a military weapon. Hahn had a strong
dislike for Adolf Hitler and his government
and told a friend: "If my work would lead to Hitler having
an atomic bomb I would kill myself."
In
April, 1945, Allied forces arrested German scientists such as Hahn,
Werner Heisenberg, Carl
von Weizsacker, Max von Laue, Karl
Wirtz, and Walter Gerlach. These
men were now taken to England where they were questioned to see
if they had discovered how to make atomic weapons.
When
he was released Hahn became president of the Max Planck Society
for the Advancement of Science. In 1966 Hahn shared with Lise
Meitner and Fritz Strassmann
the
Enrico Fermi Award. Otto Hahn died in West Germany on 28th July,
1968.
(1)
Hans Geiger was in the German Army with Otto Hahn during the First
World War. In 1917 he wrote a letter to Ernest
Rutherford.
I think nearly everyone of my colleagues whom you know is in
the field. Dr. Rumelin (also Reinganum and Glatzel) fell in one
of the first months of the war. W. H. Schmidt is also dead; but
from what I have heard he must have been in a very bad and hopeless
condition all last year and so it was perhaps the best for him.
I sometimes hear from Professor Hahn who seems to stand the dangers
of war very well and is apparently quite happy in his military position.
(2)
While in England the captured German scientists were secretly taped
to discover how much they knew about atomic weapons. This included
Otto Hahn, Werner Heisenberg, Carl
von Weizsacker, Max von Laue and
Karl Wirtz.
Otto Hahn: If the Americans have a uranium bomb then you're
all second-raters.
Werner
Heisenberg: Did they use the word uranium in connection with this
atomic bomb?
Otto
Hahn: No.
Werner
Heisenberg: Then it's got nothing to do with atoms, but the equivalent
of 20,000 tons of high explosive is terrific. All I can suggest,
is that some dilettante in America knows it has the equivalent of
20,000 tons of high explosive and in reality, it doesn't work at
all.
Otto
Hahn: At any rate Heisenberg, you're just second-raters, and you
may as well pack up.
Werner
Heisenberg: I quite agree. I am willing to believe that it is a
high pressure bomb and I don't believe that it has anything to do
with uranium but that it is a chemical thing where they have enormously
increased the whole explosion.
Karl
Witz: I'm glad we didn't have it.
Carl
von Weizsacker: I think it's dreadful of the Americans to have done
it. I think it is madness on their part.
Werner
Heisenberg: One can't say that. One could equally well say, "That's
the quickest way of ending the war."
Otto
Hahn: That's what consoles me.
Werner
Heisenberg: I believe the reason we didn't do it was because all
the physicists didn't want to do it, on principle. If we had all
wanted Germany to win the war we could have succeeded.
Otto
Hahn: I don't believe that, but I am thankful we didn't succeed.
