Hyperfine Structure Constants For High Excited Levels Of Neutral And Singly Ionized Cobalt

With the rapid development of laser spectroscopy technology and the continuous improvement of the resolution and signal-to-noise ratio of astrophysical spectra,people have aroused widespread interest in atomic structure analysis.The research and measurement of hyperfine structure(HFS)has important research significance and application value in many fields such as atomic physics,nuclear physics,theoretical physics,electrodynamics,cosmological measurement,and atomic spectroscopy.This research can not only help people understand the complex internal structure of the atoms,provide a lot of information about the atom and the nucleus,but also enhance the understanding of the QED effect,the electronic correlation model and the relativistic effect.Due to the increasing demand for the abundance of stellar elements in astrophysics,in order to extract more effective information from the high-resolution celestial spectrum,in addition to the basic atomic data such as wavelength and oscillator strength,the spectral line broadening effect,such as the isotope shift,the Zeeman effect and the hyperfine structure,needs to be considered more carefully in the analysis process.Therefore,more accurate HFS constants are indispensable atomic data for accurate calculation of celestial abundance,which is of great theoretical and practical significance for the development of astrophysics.In recent years,HFS research on many atoms and ions has increased dramatically.At present,the HFS constants of cobalt atoms(Co I)and cobalt monovalent ions(Co II)energy levels are not very complete,although there have been many international research groups that have carried out a lot of research work on the HFS of Co I and Co II,but for many highly excited state energy levels,there are still insufficient HFS constants.So far,as far as we know,the HFS constants of 300 Co I and 28 Co II energy levels have been reported in the literature.For the currently known 393 Co I and 480 Co II energy levels,there are still many HFS constants of energy levels need to be analyzed.In this paper,we obtained the Fourier transform spectra(FTS)of cobalt from the National Solar Observatory(NSO)database(http://diglib.nso.edu/).We used the least square method to analyze multiple spectral lines in FTS,and fitting spectral lines obtained accurate magnetic dipole HFS constants A and electric quadrupole HFS constants B of Co I and Co II.In total,HFS constants A for 36 levels of Co I from0.00 to 60262.463 cm^-1and for 61 levels of Co II from 11651.277 to 85876.271 cm^-1were determined.The HFS constants A values of 33 Co I and 58 Co II energy levels are reported for the first time,as far as we know.For the HFS constants A of 3 Co I and 3 Co II energy levels that have been reported in the literature,the results obtained in this paper are highly consistent with the results reported by predecessors within the allowable error range.