All Figures

Figure 1: 15 Å region of And with RGS2. Placement of a constant source continuum with median values using different parameters . The respective counts resulting from the different choices of  are given in the upper left. The best model with four lines is obtained for and is overplotted with dark grey. An overestimated continuum value leads to systematically underestimated 15.27/15.03 Å line count ratios hiding possible resonant scattering effects.

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In the text

	Figure 2: O  VII line fluxes converted to luminosities compared to total X-ray luminosities: The O  VII-luminosities are representative as activity indicators.
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In the text

Figure 3: Investigation of opacity effects for the Fe  XVII resonance line (  Å, f=2.66) as a function of characteristic temperatures derived from O  VIII/O  VII ( ) line ratios. Left panel: Line ratios with the Fe  XVII line at 15.27 Å (f=0.593), theoretical (low-optical depth) ratios from APEC, Chianti, and MEKAL, and solar measurements from Saba et al. (1999) (shaded area). Right panel: Line ratios with the Fe  XVII line at 16.78 Å (f=0.01). Same as in the left panel with additionally new calculations by Doron & Behar (2002).

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In the text

	Figure 4: Same as Fig. 3 with only the MEG and LETGS measurements. The only ratio deviating from the others is measured for EV Lac (see spectrum in Fig. 7) marked with a filled triangle.
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In the text

	Figure 5: Ratio of Fe  XVII lines at 15.27 Å and 16.78 Å, which should not be sensitive to resonant scattering (right panel: only the MEG and LETG measurements).
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In the text

	Figure 6: He-like f/r ratio for O  VII (left panel) and for Ne  IX (right panel) versus the total He-like line luminosity (r+i+f). Measurements with RGS1, RGS2, LETGS, MEG, and HEG are compared with predictions from the APEC database for temperatures , 6.3, and 6.6. assuming low densities.
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In the text

	Figure 7: Spectral region around 15 Å for EV Lac with MEG (upper panel), with the RGS2 (middle panel), and with the HEG (bottom panel). Significant differences in the 15.27 Å line compared with the 15.03 Å line can be recognized.
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In the text