Josef Mattauch

Josef Heinrich Elisabeth Mattauch was born 21 November 1895 in Ostrau, Moravia. Through the help of another professor, Mattauch spent 1927–1928 on a Rockefeller Fellowship at Caltech. There he worked with William Smythe on the development of early mass spectrometers. ==Career==

Mattauch returned to Vienna in 1928 as an unpaid lecturer. In 1938 Lise Meitner fled Germany after the Nazi occupation of Austria changed her citizenship from Austrian to German, making her subject to the antisemitic Nuremberg Laws of 1935. On 1 November 1943 Mattauch advanced to the position of deputy director of the Institute. On 15 February 1944 and again on 24 March 1944, as part of the Bombing of Berlin in World War II, the Institute suffered severe bombing damage. As of 1 October 1946, Hahn resigned as director of the Kaiser Wilhelm Institute of Chemistry, leaving Mattauch to manage the Institute. However, Mattauch suffered from tuberculosis Mattauch and Fritz Strassmann actively supported the proposed appointment of Lise Meitner as head of the physics department of the University of Mainz. Hahn and Strassman asked Meitner to return as director, but she declined their offer. Also in 1949, the renamed Max Planck Institute for Chemistry moved from Tailfingen to Mainz, Germany. At this time it consisted of two departments: Mass Spectrometry and Nuclear Physics was Mattauch's department, while Nuclear Chemistry was Strassmann's department. Mattauch retired in 1965. Christian Junge (1912-1996) succeeded Josef Mattauch as director of the Institute on October 1, 1968. Josef Heinrich Elisabeth Mattauch died 10 August 1976 in Klosterneuburg, Austria. ==Research==

Mattauch primarily focused on mass spectroscopy and research into the binding energy of atomic nuclei. The Mattauch–Herzog geometry consists of a \pi / 4\sqrt{2} radian electric sector, a drift length which is followed by a right angle (\pi / 2) magnetic sector of opposite curvature direction. The entry of the ions sorted primarily by charge into the magnetic field produces an energy focussing effect and much higher transmission than a standard energy filter. The advantage of this geometry is that the ions of different masses are all focused onto the same flat plane, which allows the use of a photographic plate or other flat detector array. He developed the Mattauch isobar rule ("Isobarenregel") in 1934, which was used to predict the radioactivity of the elements technetium and promethium. According to the rule, "if two adjacent elements on the periodic table have isotopes with the same mass number (isobars), one of the isotopes must be radioactive." Although the rule does not, in fact, hold for all elements, In the 1950s, a period of stability after the war, Mattauch was able to build a strong mass spectrometry program at the Max Planck Institute. ==Decorations and awards==

• 1957, Wilhelm Exner Medal • 1964, Austrian Decoration for Science and Art (Österreichisches Ehrenzeichen für Wissenschaft und Kunst) • 1965, Honorary doctorate from the Vienna University of Technology ==References==