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How did Otto Hahn and Fritz Strassmann discover nuclear fission?

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Atomic bomb — atomic bomb The first atomic bomb test, near Alamogordo, New Mexico, July 16, 1945.

Otto Hahn and Fritz Strassmann discovered nuclear fission in 1938 while investigating the products of uranium bombarded by neutrons.12

Building on earlier research by Enrico Fermi and a clue from Irène Joliot-Curie and Pavle Savić, Hahn and Strassmann used advanced radiochemical techniques to analyze the resulting substances. They applied carrier and tracer methods to identify the products, as the amounts were too small to detect directly. Contrary to the prevailing belief that they had produced transuranium elements, they obtained conclusive evidence that one of the products was a radioactive isotope of barium, a much lighter element.134

This result indicated that the uranium nucleus had split into two smaller pieces. Hahn shared these findings with his former colleague Lise Meitner, who, along with her nephew Otto Frisch, provided the theoretical interpretation of the process, coining the term "fission" to describe the disintegration of a heavy nucleus into two lighter ones.1235