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标题：K-shell photoabsorption and photoionization of trace elements
其他标题：III. Isoelectronic sequences with electron number 19 ≤N≤ 26⋆
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作者：C. Mendoza ; M. A. Bautista ; P. Palmeri 等
期刊名称：Astronomy & Astrophysics
印刷版ISSN：0004-6361
电子版ISSN：1432-0746
出版年度：2018
卷号：616
DOI：10.1051/0004-6361/201832939
语种：English
出版社：EDP Sciences
摘要：Context. This is the final report of a three-paper series on the K-shell photoabsorption and photoionization of trace elements (low cosmic abundance), namely F, Na, P, Cl, K, Sc, Ti, V, Cr, Mn, Co, Cu, and Zn. K lines and edges from such elements are observed in the X-ray spectra of supernova remnants, galaxy clusters, and accreting black holes and neutron stars, their diagnostic potential being limited by poor atomic data.Aims. We here complete the previously reported radiative datasets with new photoabsorption and photoionization cross sections for isoelectronic sequences with electron number 19 ≤N≤ 26. We also describe the access to and integrity and usability of the whole resulting atomic database.Methods. Target representations were obtained with the atomic structure code AUTOSTRUCTURE. Where possible, cross sections for ground-configuration states were computed with the Breit–PauliR-matrix method (BPRM) in either intermediate orLScoupling including damping (radiative and Auger) effects; otherwise and more generally, they were generated in the isolated-resonance approximation with AUTOSTRUCTURE.Results. Cross sections were computed with BPRM only for the K (N= 19) and Ca (N= 20) isoelectronic sequences, the latter inLScoupling. For the remaining sequences (21 ≤N≤ 26), AUTOSTRUCTURE was run inLS-coupling mode taking into account damping effects. Comparisons between these two methods for K-like ZnXIIand Ca-like ZnXIshow that to ensure reasonable accuracy, theLScalculations must be performed taking into account the non-fine-structure relativistic corrections. The original data structures of the BPRM and AUTOSTRUCTURE output files, namely photoabsorption and total and partial photoionization cross sections, are maintained but supplemented with files detailing the target (NT-electron system, whereNT=N− 1) representations and photon states (N-electron system).Conclusions. We conclude that because of the large target size, the photoionization of ions withN> 20 involving inner-shell excitations rapidly leads to untractable BPRM calculations, and is then more effectively treated in the isolated resonance approximation with AUTOSTRUCTURE. This latter approximation by no means involves small calculations as Auger damping must be explicitly specified in the intricate decay routes.
关键词：enatomic dataX-rays: general