High accuracy characterisation for the absolute energy of scandium Kα
| Autor: | Christopher T. Chantler, L. F. Smale, H A Melia, Jonathan W. Dean |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Physics
X-ray spectroscopy chemistry.chemical_element Germanium 010403 inorganic & nuclear chemistry Condensed Matter Physics 01 natural sciences Atomic and Molecular Physics and Optics Spectral line 0104 chemical sciences chemistry 0103 physical sciences Calibration K-alpha Scandium Emission spectrum Atomic physics 010306 general physics Spectroscopy |
| Zdroj: | Journal of Physics B: Atomic, Molecular and Optical Physics. 52:165002 |
| ISSN: | 1361-6455 0953-4075 |
| DOI: | 10.1088/1361-6455/ab29b1 |
| Popis: | This work reports the absolute characterisation of the Sc Kα profile. All component peaks are characterised for the first time. The satellite component centroids, line-widths, and relative intensities are determined. Energies are calibrated on an absolute basis. Sc and peak energies of 4090.699(10) eV and 4085.926(18) eV are reported, respectively, with estimated standard error uncertainties of 2.4 and 4.4 ppm. In this work, an electron gun operating at 20 kV, incident on high purity metals, produces the x-ray fluorescence, which Bragg diffracts via a Germanium (220) crystal to permit high-accuracy measurement of energy. The Kα emission spectrum of scandium (Z = 21) has not been measured in absolute energy in over 50 years. At the time the data was reported in 'x units' and the angstrom was not a well defined unit. That reported uncertainty was estimated to be approximately 50 ppm (parts per million) or 0.2 eV. The new profile characterisation combined with the absolute energy calibration provides an important definition for future studies in chemical speciation and condensed matter studies. Furthermore, the methodology described obtains a level of accuracy from relatively low energy x-rays to provide an important insight for future studies in fundamental parameters, pionic spectra and high-accuracy tests of QED. |
| Databáze: | OpenAIRE |
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