Karl Manne Georg Siegbahn

Siegbahn, Karl Manne Georg 

Born Dec. 3, 1886, in Örebro. Swedish physicist. Member of the Royal Swedish Academy of Sciences (1922). After receiving his doctorate at the University of Lund in 1911, Siegbahn remained at the university as assistant to J. R. Rydberg. Siegbahn was a professor at the University of Lund from 1920 to 1923 and at the University of Uppsala from 1923 to 1937. In 1937 he became director of the Nobel Institute of Physics of the Royal Swedish Academy of Sciences.

Siegbahn’s research from 1912 to 1937 was concerned chiefly with X-ray spectroscopy. From 1937 he worked primarily in nuclear spectroscopy. Using methods and precision apparatus he developed, Siegbahn studied X-ray spectra and made a substantial contribution to knowledge about such spectra. He was the first to observe and measure the dispersion of X rays, and he provided experimental proof that the index of refraction of X rays is less than 1. He made a diffraction grating with very closely spaced rulings (1,800 lines/mm) and used it to measure the wavelength of soft X rays. He is regarded as the founder of nuclear spectroscopy.

Siegbahn received a Nobel Prize in 1924. He became a foreign member of the Royal Society of London in 1933 and of the Academy of Sciences of the USSR in 1958.

WORKS

Spektroskopie der Rontgenstrahlen. Berlin, 1924. Second ed.: Berlin, 1931.

I. D. ROZHANSKII