Astronomy & Astrophysics

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$\begin{figure} \par\includegraphics[angle=90,width=7.5cm]{H4467F1a.ps}\vspace*{1... ...}\vspace*{1mm} \includegraphics[angle=90,width=7.2cm]{H4467F1c.ps} \end{figure}$ Figure 1: X-ray light curves from the observations analyzed in this work: a) and b): XMM/EPIC-pn light curves of rev. #091 and #205; c): Chandra/HETG 1st order light curve of AB Dor A. The lower axis indicates time in days, and the upper axis reports the rotational phase, using ephemeris by Innis et al. (1988). Variations of 35-50% in the flux level are found during each of the three observations.
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In the text

$\begin{figure} \par\resizebox{17.8cm}{!}{\includegraphics[angle=270]{H4467F2.ps}} \end{figure}$ Figure 2: RGS 1 first order spectrum of AB Dor from the revolution #091 observation. The dashed line represents the continuum predicted by the EMD. A false continuum is created by the extended instrumental line profiles.
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In the text

$\begin{figure} \par\resizebox{8.8cm}{!}{\includegraphics[angle=270]{H4467F3.ps}} \end{figure}$ Figure 3: RGS 1 second order spectrum of AB Dor from the rev. #091 observation.
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In the text

$\begin{figure} \par\resizebox{18cm}{!}{\includegraphics[angle=270]{H4467F4.ps}} \end{figure}$ Figure 4: Chandra/MEG spectrum of AB Dor. The dashed line represents the continuum predicted by the EMD.
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In the text

$\begin{figure} \par\resizebox{18cm}{!}{\includegraphics[angle=270]{H4467F5a.ps} \includegraphics[angle=270]{H4467F5b.ps}} \end{figure}$ Figure 5: Section of the RGS 2 spectrum of rev. # 091, showing the fit to the line Fe XXIII $\lambda$ 11.736 alone (left), and including important lines in the same wavelength region (right). The flux measured for the Fe XXIII $\lambda$ 11.736 line is a 43% higher if the additional lines considered in the right panel are not included in the fit. The presence of a false continuum created by the LSF of adjacent lines influences the measurement of every line. A dashed line indicates the continuum predicted from the EMD.
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In the text

$\begin{figure} \par\resizebox{7.9cm}{!}{\includegraphics{H4467F6.eps}} \end{figure}$ Figure 6: Upper: EMD derived from Chandra/HETG data. Thin lines represent the relative contribution function for each ion (the emissivity function multiplied by the EMD at each point). Small numbers indicate the ionization stages of the species. Lower: observed to predicted line flux ratios for the ion stages in the upper figure. The dotted lines denote a factor of 2.
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In the text

$\begin{figure} \par\resizebox{7.9cm}{!}{\includegraphics{H4467F7.eps}} \end{figure}$ Figure 7: Same as Fig. 6, for the XMM/RGS data during rev. # 091.
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In the text

$\begin{figure} \par\resizebox{7.9cm}{!}{\includegraphics{H4467F8.eps}} \end{figure}$ Figure 8: Flux ratios corresponding to the measurements of the second order of the XMM/RGS data during rev. #091 (see Table 5), using the EMD and abundances derived from the line fluxes in the first order.
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In the text

$\begin{figure} \par\resizebox{7.9cm}{!}{\includegraphics[angle=90]{H4467F9.eps}} \end{figure}$ Figure 9: Electron densities from He-like triplets (see Table 7).
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In the text

$\begin{figure} \par\resizebox{8cm}{!}{\includegraphics[angle=90]{H4467F10.eps} } \end{figure}$ Figure 10: Electron densities from Fe XXI (dashed lines) and Fe XXII (solid lines) lines ratios, as indicated in Table 8.
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In the text

$\begin{figure} \par\resizebox{8cm}{!}{\includegraphics[angle=90]{H4467F11.eps}} \end{figure}$ Figure 11: Comparison of EMDs derived from different instruments. The EMD from EUVE observations (Sanz-Forcada et al. 2002) was scaled for a coronal abundance of $\rm [Fe/H]=-0.57$ . Representative $1-\sigma$ error bars are shown for the Chandra/HETG EMD only (note that these error bars are not independent, see text).
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In the text

$\begin{figure} \par\resizebox{8cm}{!}{\includegraphics{H4467F12.eps}} \end{figure}$ Figure 12: Element abundances in the corona of AB Dor, with respect to solar photosphere. A dashed line indicates the solar photospheric abundance (Anders & Grevesse 1989).
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In the text

$\begin{figure} \par\resizebox{7.7cm}{!}{\includegraphics[angle=90]{H4467F13.eps}} \end{figure}$ Figure 13: Electron pressure derived from the electron densities at different temperatures (see text). Last two points represent averages over different density values in Table 8.
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In the text

$\begin{figure} \par\resizebox{17.8cm}{!}{\includegraphics[angle=270]{H4467F2.ps}} \end{figure}$	Figure 2: RGS 1 first order spectrum of AB Dor from the revolution #091 observation. The dashed line represents the continuum predicted by the EMD. A false continuum is created by the extended instrumental line profiles.
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$\begin{figure} \par\resizebox{8.8cm}{!}{\includegraphics[angle=270]{H4467F3.ps}} \end{figure}$	Figure 3: RGS 1 second order spectrum of AB Dor from the rev. #091 observation.
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$\begin{figure} \par\resizebox{18cm}{!}{\includegraphics[angle=270]{H4467F4.ps}} \end{figure}$	Figure 4: Chandra/MEG spectrum of AB Dor. The dashed line represents the continuum predicted by the EMD.
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$\begin{figure} \par\resizebox{7.9cm}{!}{\includegraphics{H4467F6.eps}} \end{figure}$	Figure 6: Upper: EMD derived from Chandra/HETG data. Thin lines represent the relative contribution function for each ion (the emissivity function multiplied by the EMD at each point). Small numbers indicate the ionization stages of the species. Lower: observed to predicted line flux ratios for the ion stages in the upper figure. The dotted lines denote a factor of 2.
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$\begin{figure} \par\resizebox{7.9cm}{!}{\includegraphics{H4467F7.eps}} \end{figure}$	Figure 7: Same as Fig. 6, for the XMM/RGS data during rev. # 091.
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$\begin{figure} \par\resizebox{7.9cm}{!}{\includegraphics{H4467F8.eps}} \end{figure}$	Figure 8: Flux ratios corresponding to the measurements of the second order of the XMM/RGS data during rev. #091 (see Table 5), using the EMD and abundances derived from the line fluxes in the first order.
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$\begin{figure} \par\resizebox{7.9cm}{!}{\includegraphics[angle=90]{H4467F9.eps}} \end{figure}$	Figure 9: Electron densities from He-like triplets (see Table 7).
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$\begin{figure} \par\resizebox{8cm}{!}{\includegraphics[angle=90]{H4467F10.eps} } \end{figure}$	Figure 10: Electron densities from Fe XXI (dashed lines) and Fe XXII (solid lines) lines ratios, as indicated in Table 8.
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$\begin{figure} \par\resizebox{8cm}{!}{\includegraphics[angle=90]{H4467F11.eps}} \end{figure}$	Figure 11: Comparison of EMDs derived from different instruments. The EMD from EUVE observations (Sanz-Forcada et al. 2002) was scaled for a coronal abundance of $\rm [Fe/H]=-0.57$ . Representative $1-\sigma$ error bars are shown for the Chandra/HETG EMD only (note that these error bars are not independent, see text).
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$\begin{figure} \par\resizebox{8cm}{!}{\includegraphics{H4467F12.eps}} \end{figure}$	Figure 12: Element abundances in the corona of AB Dor, with respect to solar photosphere. A dashed line indicates the solar photospheric abundance (Anders & Grevesse 1989).
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$\begin{figure} \par\resizebox{7.7cm}{!}{\includegraphics[angle=90]{H4467F13.eps}} \end{figure}$	Figure 13: Electron pressure derived from the electron densities at different temperatures (see text). Last two points represent averages over different density values in Table 8.
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