On the sizes of stellar X-ray coronae

  title={On the sizes of stellar X-ray coronae},
  author={J.‐U. Ness and Manuel Gudel and Juergen H.M.M. Schmitt and M. Audard and Alessandra Telleschi},
  journal={Astronomy and Astrophysics},
Spatial information from stellar X-ray coronae cannot be assessed directly, but scaling laws from the solar corona make it possible to estimate sizes of stellar coronae from the physical parameters temperature and density. While coronal plasma temperatures have long been available, we concentrate on the newly available density measurements from line fluxes of X-ray lines measured for a large sample of stellar coronae with the Chandra and XMM-Newton gratings. We compiled a set of 64 grating… Expand
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Recent analysis of high-resolution Chandra X-ray spectra has shown that the Ne/O abundance ratio is remarkably constant in stellar coronae. Based on this result, we point out the utility of the Ne/OExpand
High-resolution X-ray spectroscopy of T Tauri stars in the Taurus-Auriga complex
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X-ray emission processes in stars and their immediate environment
  • P. Testa
  • Physics, Medicine
  • Proceedings of the National Academy of Sciences
  • 2010
The progress made in the study of high energy stellar physics and its impact in a wider astrophysical context is discussed, focusing on the role of spectral diagnostics now accessible. Expand


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