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arXiv · 2011.15111

Measurements of the Hyperfine Structure of Atomic Energy Levels in Co II

Milan Ding·Juliet C. Pickering
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Abstract

Analysis of hyperfine structure constants of singly ionised cobalt (Co II) were performed on cobalt spectra measured by Fourier transform spectrometers in the region $3000-63000$ cm$^{-1}$ ($3333-159$ nm). Fits to over $700$ spectral lines led to measurements of $292$ magnetic dipole hyperfine interaction $A$ constants, with values between $-32.5$ mK and $59.5$ mK ($1$ mK $=0.001$ cm$^{-1}$). Uncertainties of $255$ A constants were between $\pm0.4$ mK and $\pm3.0$ mK, the remaining $37$ ranged up to $\pm7$ mK. The electric quadrupole hyperfine interaction $B$ constant could be estimated for only $1$ energy level. The number of Co II levels with known $A$ values has now increased tenfold, improving and enabling the wider, more reliable and accurate application of Co II in astronomical chemical abundance analyses.

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Milan Ding, Juliet C. Pickering. 2020-11-30. Measurements of the Hyperfine Structure of Atomic Energy Levels in Co II. https://doi.org/10.3847/1538-4365/abbdf8

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