Advanced Atomic Calculations for the atomic structure of Iron Ions

Rawaa Yaseen Taha

Iron (Z= 26) has a high abundance in cosmic environments, that is why the X- ray spectra about a huge variety about astrophysical sources hold proven the riches concerning blood discharge lines. Recently, features of iron ions have attracted many experimentalists to perform laboratory studies to identify transition lines of iron ions under different conditions. However experimental spectra are often complicated which makes there difficult to be interpreted. Therefore performing theoretical calculations become crucial to identify all atomic structure properties of iron ions ions and break down the complexity of the experimental spectra. This research is focused on calculation and identification of the spectral features of Fe ions from Mn like Fe (Fe+ 14) and their spectral range. Two different theories in atomic physics were used to produce atomic structure and spectra database for the selected Fe ions. Using Cowan code the superposition of configuration method, with a first order relativistic correction method and the other is a fully relativistic multi- configuration interaction method. Using HTAC atomic structure code. The analysis of 14 Fe ions synthetic spectra for electric dipole transitions showed the presence of a wide variety of ionization stages from Mn- like to Mg- like Fe in the wide spectral range from soft Xray to extreme ultraviolet. The majority of the lines in the Mn like Fe, Cr like Fe, V like Fe and Ti like Fe ions spectra were identified and assigned to the 3d and transitions. The lines in the Sc like Fe ion Spectra were identified and assigned to the 3d  nf transitions. The lines in the Ca like Fe, K like Fe ions spectra were identified and assigned to the 4S  np transitions. The lines in the Ar like Fe, Cl like Fe, S like Fe, P like Fe, Si like Fe, Al like Fe ions spectra were identified and assigned to the 3p  nd transitions. The last ion Mg like Fe ions spectra were identified and assigned to the 3S  np transitions. The transition energies, transition rates and wavelengths calculated in the two approaches were compared with each other and showed a good agreement with a small shift for some transition lines of some ions. Another comparison was performed between the calculated data and the available empirical values yet with results out of sordid recent calculations.

Volume 12 | 02-Special Issue

Pages: 475-489

DOI: 10.5373/JARDCS/V12SP2/SP20201095