Confronting atomic data with Fe L-shell spectra of stellar coronae

E. Behar; J. Cottam; J. R. Peterson; M. Sako; S. M. Kahn; A. Bar-Shalom; M. Klapisch; A. C. Brinkman

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Confronting atomic data with Fe L-shell spectra of stellar coronae

E. Behar·J. Cottam·J. R. Peterson·M. Sako·S. M. Kahn·A. Bar-Shalom·M. Klapisch·A. C. Brinkman

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Abstract

It is common to suggest the uncertainties in the atomic data for explaining difficulties that arise in interpreting astrophysical x-ray spectra. The atomic data for the Fe L-shell ions have, over the years, been considered particularly suspect. In this paper, we confront Fe-L spectra calculated using the HULLAC atomic code assuming coronal conditions with recent observations of the stellar coronae of Capella and HR 1099, obtained with the high-resolution grating spectrometers on board Chandra and XMM-Newton. We find very good agreement, which indicates that Fe-L transition rates calculated with state-of-the-art codes, can generally be trusted in the analysis of x-ray spectra.

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E. Behar, J. Cottam, J. R. Peterson, M. Sako, S. M. Kahn, A. Bar-Shalom, M. Klapisch, A. C. Brinkman. 2001-06-25. Confronting atomic data with Fe L-shell spectra of stellar coronae. https://arxiv.org/abs/astro-ph/0106448

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