Arthur Jeffrey Dempster

AJ Dempster

Arthur Jeffrey Dempster (born August 14, 1886 in Toronto , Ontario , † March 11, 1950 in Stuart , Florida ) was a Canadian-American physicist .

Dempster's 1918 mass spectrometer

Life

Dempster studied at the University of Toronto with a bachelor's degree in 1909 and a master's degree in 1910, continued his studies in Germany and received his doctorate in 1916 at the University of Chicago . From 1919 he taught at the University of Chicago. In 1918 he developed the first modern mass spectrometer and in 1936, like Kenneth Bainbridge and Josef Mattauch, a double focusing mass spectrometer. He used mass spectrometry to search for stable isotopes and to determine their relative abundances. In doing so, he discovered more isotopes than any other scientist with the exception of Francis William Aston , the inventor of the principle. In 1935 he discovered the uranium - isotope ²³⁵ U.

In World War II Dempster worked on the Manhattan Project with. Since 1921 he was a fellow of the American Physical Society , of which he was president in 1944. Since 1932 he was a member of the American Philosophical Society and since 1937 of the National Academy of Sciences .

Web links

• Entry in the Encyclopædia Britannica (English)