Nuclear fission
Hahn and Strassmann publish chemical evidence of uranium fission products
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Original prompt & settings (JSON) ↗The paper that announced the chemical clue to fission never used the word 'fission' — that came just over five weeks later, when Lise Meitner and Otto Frisch published their physical interpretation.
6 January 1939: five pages in Die Naturwissenschaften
On 6 January 1939, Die Naturwissenschaften published Otto Hahn and Fritz Strassmann's jointly authored paper on the alkaline-earth products formed when uranium is irradiated with neutrons. It ran in volume 27, issue 1, pages 11–15.
The manuscript had been submitted on 22 December 1938 — only fifteen days between submission and print.
Barium, not radium
The paper reported chemical evidence that compelled its authors to identify the unexpected radioactive material as barium rather than the much heavier radium they had expected. That was the whole claim: chemistry, from two Berlin chemists at the Kaiser Wilhelm Institute for Chemistry.
What the paper did not contain was a physical explanation for how a uranium nucleus could yield an element roughly halfway down the periodic table.
Just over five weeks to an interpretation
Publication put the experimental result in front of the physics community before Meitner and Frisch's physical interpretation appeared in print. Lise Meitner, who had received Hahn's report in exile, worked out the interpretation with Otto Robert Frisch.
Their physical explanation, and the term 'fission', appeared in Nature on 11 February 1939.
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