A complete set of radiative and Auger rates for K-vacancy states in Fe XVIII–Fe XXV

Abstract

Abstract.A complete set of level energies, wavelengths, A-values, and total and partial Auger rates have been computed for transitions involving the K-vacancy states within the n = 2 complex of Fe -Fe . Three different standard numerical packages are used for this purpose, namely , the Breit-Pauli R-matrix suite () and , which allow reliable estimates of the physical effects involved and of the accuracy of the resulting data sets. The Breit interaction is taken into account because its contributions to the small A-values and partial Auger rates cannot be neglected with increasing electron occupancy. Semiempirical adjustments can also lead to large differences in both the radiative and Auger decay data of strongly mixed levels. Several experimental level energies and wavelengths are questioned, and significant discrepancies are found with previously computed decay rates that are attributed to numerical problems. The statistical accuracy of the present level energies and wavelengths is ranked at ±3 eV and ±2 mÅ, respectively, and that for A-values and partial Auger rates greater than 10 13 s −1 at better than 20%.

Atomic decay data for modeling K lines of iron peak and light odd-Zelements

“…They also estimated theoretical values as ratios of radiative transition probabilities using the MCDF method with two different optimization options (EAL and OL). We report the transition probability ratios calculated with HFR in this work (Z = 9, 11, 15, 17, 19, 21−25, 27, 29, 30, 32) and in our previous studies (Palmeri et al 2003a(Palmeri et al , 2008a(Palmeri et al , 2011. We have also carried out MCDF-EAL calculations in fluorine, phosphorus, Fig.…”

“…For ions with Z c ≤ 15, the experimental wavelengths λ EXP i are taken from the laser-produced plasma experiment of Faenov et al (1994) and the plasma focus discharge in argon of Biémont et al (2000); for ions with Z c > 15, the wavelengths measured using an EBIT are considered (Beiersdorfer et al 1991;Smith et al 1995;Decaux et al 1997). The HFR wavelengths λ HFR i are calculated in this work for phosphorus, vanadium and cobalt; in Palmeri et al (2003a) for iron; in Palmeri et al (2008a) for magnesium, silicon, sulphur and argon and in Palmeri et al (2011) for aluminium. The experimental error bars are also displayed.…”

“…Following extensive work by Palmeri et al (2002Palmeri et al ( , 2003a, Bautista et al (2003Bautista et al ( , 2004, Mendoza et al (2004) and Kallman et al (2004) on Fe K lines; García et al (2005) on the K-shell photoabsorption of O ions; Palmeri et al (2008a) on the Ne, Mg, Si, S, Ar and Ca K lines; Palmeri et al (2008b) on the Ni K lines; García et al (2009) on the K-shell photoionization and photoabsorption of N ions; by Witthoeft et al (2009) …”

K-shell energy levels and radiative rates for transitions in Si ix

“…The effects of configuration interaction from high-energy configurations have been investigated in iron K-shell data by Bautista et al (2003) and Palmeri et al (2003), who found that the configurations with n = 3 have little effect on the accuracy of the 1s−2p transition atomic data from Fe xviii to Fe xxv, either for energy levels or for radiative rates. For example, differences lower than 2% are found for radiative rates when the n = 3 configurations are included in Fe xxiv .…”

Iron Kα Spectra from an Atomic Modeling Perspective

“…Unfortunately, many potentially useful plasma diagnostics become obscured by detectors with poor resolution, which, in turn, tends to inhibit the development of these diagnostics. In light of the imminent launch of Astro-E 2, with a resolving power « 6 eV, this situation is improving, and detailed calculations of the atomic physics processes associated with Fe K spectral formation, using state-of-the-art computer codes, are now becoming available (for example, Palmeri et al 2003).…”