Barkla, Charles

Barkla, Charles Glover (1877-1944) was born in Widnes, Lancashire, England. After obtaining his master s degree in physics he went to work in the Cavendish Laboratory with J.J. Thomson. In 1913 he accepted the position of Chair in Natural Philosophy in the University of Edinburgh in Scotland and he remained there until he died. He was awarded the 1917 Nobel Prize in Physics for his discovery of the characteristic Rbntgen radiation of the elements. 

Charles Barkla, an early X-ray spectroscopist, introduced this terminology for electron shells in 1911. We still use it today to designate characteristic X-rays in both X-ray diffraction and in chemical analysis using electron microscopy. Barkla named the two types of characteristic X-ray emissions he observed as the K-series and L-series. He later predicted that an M-series and a J-series might exist. An M-series was subsequently discovered, but no J-series. The K shell is hence the first shell. 

Aage N. Bohr, Ben R. Mottelson, James Rainwater 1917 Charles Glover Barkla... 

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