December 3, 1886 - Birth of Karl Manne Siegbahn, Nobel Prize for his contribution to the field of X-ray spectroscopy

Karl Manne Georg Siegbahn received his doctorate in 1911 with his thesis entitled ‘Measurements of the magnetic field’ and since then has devoted himself to teaching. He was also the first head of the Physics Department at the Nobel Institute.

His scientific research focused on the field of X-ray spectroscopy, a technique for studying the electronic structure of substances by means of X-ray excitation. In this field, he developed new methods and instruments, such as spectrographs, vacuum pumps, and X-ray tubes, which greatly increased the precision of his measurements and made it possible to obtain a virtually complete knowledge of the energy levels of electrons in atoms.

He also developed the so-called ‘Siegbahn notation’ for cataloguing the X-ray spectral lines of the chemical elements. This notation is still used today.

His precise measurements made theoretical breakthroughs in atomic and quantum physics possible. For this, he was awarded the Nobel Prize in Physics in 1924. Curiously, he received the prize a year later, as the Nobel Committee for Physics considered that none of the candidates, including Karl Siegbahn, met the criteria specified by Alfred Nobel, so, in accordance with the statutes of the Nobel Foundation, the prize was suspended until the following year.

He had two sons, one of them physicist Kai Manne Börje Siegbahn, who was awarded the Nobel Prize in Physics like him in 1981.

If you want to know more about this scientist, click on the following link: Karl Manne Siegbahn