Walther Bothe

Walther Bothe
Walther Bothe in the 1950s
Born	(1891-01-08)8 January 1891 Oranienburg, German Empire
Died	8 February 1957(1957-02-08) (aged 66) Heidelberg, West Germany
Nationality	Germany
Fields	Physics, mathematics, chemistry
Institutions	University of Berlin University of Giessen University of Heidelberg Max Planck Institute for Medical Research
Alma mater	University of Berlin
Doctoral advisor	Max Planck
Doctoral students	Hans Ritter von Baeyer
Known for	Coincidence circuit
Notable awards	Nobel Prize for Physics (1954) Max Planck Medal (1953)

Walther Wilhelm Georg Bothe (8 January 1891 – 8 February 1957) was a German nuclear physicist, who shared the Nobel Prize in Physics in 1954 with Max Born.

In 1913, he joined the newly created Laboratory for Radioactivity at the Reich Physical and Technical Institute (PTR), where he remained until 1930, the latter few years as the director of the laboratory. He served in the military during World War I from 1914, and he was a prisoner of war of the Russians, returning to Germany in 1920. Upon his return to the laboratory, he developed and applied coincidence methods to the study of nuclear reactions, the Compton effect, cosmic rays, and the wave–particle duality of radiation, for which he would receive the Nobel Prize in Physics in 1954.

In 1930 he became a full professor and director of the physics department at the University of Giessen. In 1932, he became director of the Physical and Radiological Institute at the University of Heidelberg. He was driven out of this position by elements of the deutsche Physik movement. To preclude his emigration from Germany, he was appointed director of the Physics Institute of the Kaiser Wilhelm Institute for Medical Research (KWImF) in Heidelberg. There, he built the first operational cyclotron in Germany. Furthermore, he became a principal in the German nuclear energy project, also known as the Uranium Club, which was started in 1939 under the supervision of the Army Ordnance Office.

In 1946, in addition to his directorship of the Physics Institute at the KWImf, he was reinstated as a professor at the University of Heidelberg. From 1956 to 1957, he was a member of the Nuclear Physics Working Group in Germany.

In the year after Bothe's death, his Physics Institute at the KWImF was elevated to the status of a new institute under the Max Planck Society and it then became the Max Planck Institute for Nuclear Physics. Its main building was later named Bothe laboratory.

Bothe was born to Fredrich Bothe and Charlotte Hartung. From 1908 to 1912, Bothe studied at the Friedrich-Wilhelms-Universität (today, the Humboldt-Universität zu Berlin). In 1913, he was Max Planck's teaching assistant. He was awarded his doctorate, in 1914, under Planck.

In 1913, Bothe joined the Physikalisch-Technische Reichsanstalt (PTR, Reich Physical and Technical Institute; today, the Physikalisch-Technische Bundesanstalt), where he stayed until 1930. Hans Geiger had been appointed director of the new Laboratory for Radioactivity there in 1912. At the PTR, Bothe was an assistant to Geiger from 1913 to 1920, a scientific member of Geiger's staff from 1920 to 1927, and from 1927 to 1930 he succeeded Geiger as director of the Laboratory for Radioactivity.