The Density of Coronal Plasma in Active Stellar Coronae

@article{Testa2004TheDO,
  title={The Density of Coronal Plasma in Active Stellar Coronae},
  author={P. Testa and J. Drake and G. Peres},
  journal={The Astrophysical Journal},
  year={2004},
  volume={617},
  pages={508-530}
}
We have analyzed high-resolution X-ray spectra of a sample of 22 active stars observed with the High Energy Transmission Grating Spectrometer on Chandra in order to investigate their coronal plasma density. Densities were investigated using the lines of the He-like ions O VII, Mg XI, and Si XIII. Si XIII lines in all stars of the sample are compatible with the low-density limit (i.e., ne 1013 cm-3), casting some doubt on results based on lower resolution Extreme Ultraviolet Explorer (EUVE… Expand
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