EXAMPLE FISSION URANIUM SERIES
EXAMPLE FISSION URANIUM CRACK

They stopped at a tree stump to do some calculations. They went for a walk in the snow to talk about the matter, Frisch on skis, Meitner keeping up on foot. They knew that Hahn was a good chemist and had not made a mistake, but the results didn't make sense. Meitner shared Hahn's letter with Frisch. Over the Christmas holiday, Meitner had a visit from her nephew, Otto Frisch, a physicist who worked in Copenhagen at Niels Bohr's institute. Hahn sent a letter to Meitner describing the puzzling finding.

EXAMPLE FISSION URANIUM CRACK

They couldnвЂ™t explain it, since it was thought that a tiny neutron couldn't possibly cause the nucleus to crack in two to produce much lighter elements. In December 1938, Hahn and Strassmann, continuing their experiments bombarding uranium with neutrons, found what appeared to be isotopes of barium among the decay products. She kept up her correspondence with Hahn, and continued to advise him about their joint research. She took a position in Stockholm at the Nobel Institute for Physics, but she had few resources for her research there, and felt unwelcome and isolated. Her research was her whole life, and she had tried to hang on to her position as long as possible, but when it became clear that she would be in danger, she left hastily, with just two small suitcases. Meitner, who had Jewish ancestry, worked at the KWI until July 1938, when she was forced to flee from the Nazis.

Hahn carried out the careful chemical analysis Meitner, the physicist, explained the nuclear processes involved.

EXAMPLE FISSION URANIUM SERIES

Her paper was largely ignored, and no one, not even Noddack herself, followed up on the idea.ДЇollowing FermiвЂ™s work, Meitner and Hahn, along with chemist Fritz Strassmann, also began bombarding uranium and other elements with neutrons and identifying the series of decay products. However, one chemist, Ida Noddack, pointed out that Fermi hadnвЂ™t ruled out the possibility that in his reactions, the uranium might actually have broken up into lighter elements, though she didnвЂ™t propose any theoretical basis for how that could happen. Most scientists thought that hitting a large nucleus like uranium with a neutron could only induce small changes in the number of neutrons or protons. In 1934 Enrico Fermi bombarded uranium with neutrons, producing what he thought were the first elements heavier than uranium. Upon returning to Berlin she was made head of a physics section at the KWI, where she did research in nuclear physics.ДЄfter the neutron was discovered 1932, scientists realized that it would make a good probe of the atomic nucleus. During World War I Meitner volunteered as an x-ray nurse in the Austrian army.

In 1912 the Kaiser Wilhelm Institute for chemistry was established, and she obtained a position there. Meitner was shy, but soon became a friend and collaborator of chemist Otto Hahn. As a woman, the only position available to her at that time in Vienna was as a schoolteacher, so she went to Berlin in 1907 in search of research opportunities. She grew up in an intellectual family, and studied physics at the University of Vienna, receiving a doctorate in 1906. Trying to explain a puzzling finding made by nuclear chemist Otto Hahn in Berlin, Meitner and Frisch realized that something previously thought impossible was actually happening: that a uranium nucleus had split in two. In December 1938, over Christmas vacation, physicists Lise Meitner and Otto Frisch made a startling discovery that would immediately revolutionize nuclear physics and lead to the atomic bomb.

Example fission uranium