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arXiv · astro-ph/0201530

Elemental Abundances in Stellar Coronae with XMM-Newton

Abstract

The XMM-Newton Reflection Grating Spectrometer Team has obtained observations ofa large number of coronal sources of various activity levels, ages, and spectraltypes. In particular, X-ray bright RS CVn binary systems display saturated coronal emission with spectral lines characteristic of hot (10-30 MK) plasma. Furthermore, we have obtained XMM-Newton data from young solar analogs both within and outside the X-ray saturation regime. We have simultaneously analyzed the EPIC MOS and RGS data from these objects and have obtained coronal abundances of various elements (e.g., C, N, O, Ne, Mg, Si, Fe). We show that there is evidence for a transition from an Inverse First Ionization Potential (FIP) effect in most active stars to a ``normal'' solar-like FIP effect in less active stars. We discuss this result with regard to photospheric abundances.

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BibTeXRIS

Marc Audard, Manuel Guedel. 2002-01-31. Elemental Abundances in Stellar Coronae with XMM-Newton. https://arxiv.org/abs/astro-ph/0201530

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