Pionic Hydrogencollaboration © 2007
Webmaster: D.Gotta
Design: M.Nekipelov
For ultimate calibration purposes the energy accuracy of medium Z fluorescence X-rays should be of the order of 10 - 20 meV. It is well known that chemical shifts of up 1 eV occur for the 3d elements. It is shown that the quality of the energy determination can be improved substantially by choosing a suitable compound because the X-ray line width can be decreased by a factor of about 2 together with a reduction of satellite structures. As an example for a 3d element the case of manganese was studied in detail. Kα X-ray emission in manganese compounds Spectrochimica Acta Part B 121 (2016) 11
When searching standards for the energy calibration of exotic-atom X-rays a natural choice is Kα or Kβ fluorescence radiation from electronic atoms. However, not in all cases such transitions are suited to fulfil ultimate precision requirements. In particular, for tabulated values even the compound used in the experiment is questionable or even unknown. For scandium, e.g. it is known that significant chemical shifts occur. Secondly, the large natural line width and the dependence of satellite structures on the excitation mechanism lead to a complex line shape limiting the accuracy of the energy determination and the resolution function of crystal spectrometers. On the other hand, exotic-atom X-rays provide calibrations which applied improve the data on the fluorescence radiation itself. Here, the combination of scandium Kα and Kβ X-rays and the pionic neon (6-5) transition is discussed. Kα and Kβ X-ray emission spectra of metallic scandium Phys. Rev. A 60 60 (1999) 2018