Astronomy & Astrophysics

All Figures

$\begin{figure} \par\includegraphics[width=15.7cm,clip]{3414f1.ps} \end{figure}$ Figure 1: LETGS smoothed spectrum (positive and negative orders added) of Capella, with bin size of $0.0125~{\rm \AA}$ , collected on March 8, 2000, split into three parts. Note the different scales in each panel. The labels identify some of the strongest lines.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f2.ps} \end{figure}$ Figure 2: Emission measure distributions calculated with the MCMC method by Kashyap & Drake (1998) for the observation made on March 2000 (solid line) and for the observation made on February 2001 (dotted line). Note that we can provide error bars only for the bins ranging from $\log T=6.2$ to $\log T=7.3$ .
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f3.ps} \end{figure}$ Figure 3: Comparison between observed and predicted line fluxes vs. $T_{{\rm max}}$ (upper panel) and vs. chemical elements and, for iron, ionization stage (lower panel). Filled symbols indicate the lines included in the emission measure reconstruction, open symbols indicate those not included, and triangles indicate the long wavelength lines ( $\lambda >80~{\rm \AA}$ ).
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In the text

$\begin{figure} \par\includegraphics[width=15.6cm,clip]{3414f4.ps} \end{figure}$ Figure 4: Comparison between LETGS spectrum of Capella (with error bars), collected on March 8, 2000, and the predicted spectrum (thick line) derived from the reconstructed emission measure distribution.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f5.ps} \end{figure}$ Figure 5: Comparison between observed spectrum (solid line) and predicted continuum spectra with different iron abundances (reported in the legend) relative to the Grevesse et al. (1992) solar value. Predicted continuum spectra are generated using the em(T) and abundance values derived by the MCMC procedure, and $N_{{\rm e}}=10^{10}~{\rm cm^{-3}}$ . The best determination of the relative line to continuum ratio is achieved assuming a coronal metal abundance equal to the solar one.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f6.ps} \end{figure}$ Figure 6: Derived abundances, in solar units (Grevesse et al. 1992), vs. first ionization potential. Filled diamonds are abundances derived from the observation taken on March 2000, open diamonds the ones derived from the observation taken on February 2001.
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In the text

$\begin{figure} \par\includegraphics[width=16.5cm,clip]{3414f7.ps} \end{figure}$ Figure 7: Observed and best-fit multi-component model spectrum for the Si XIII, Mg XI, Ne IX and O VII triplets of the positive order of the observation taken on March 2000. Dotted lines represent individual lines while the horizontal line indicates the continuum.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f8.ps} \end{figure}$ Figure 8: Comparison, in $\sigma$ unit, between observed line fluxes of the two observations.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f9.ps} \end{figure}$ Figure 9: Comparison, in $\sigma$ unit, between total observed line fluxes at each $T_{{\rm max}}$ of the two observations.
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In the text

$\begin{figure} \par\includegraphics[width=16.4cm,clip]{3414f10.ps} \end{figure}$ Figure 10: Light curves and effective variability for the lines at $T_{{\rm max}}=10^{6.7}~{\rm K}$ for both the observations. The upper panels show the light curves generated collecting all the photons of selected lines with the same $T_{{\rm max}}$ (see Table 4). The lower panels show the values of effective variability $V_{{\rm eff}}/I$ found for each bin size explored. Dotted curves correspond to the statistical confidence levels at (a) 95.45%, (b) 99.73% and (c) 99.99% that the null hypothesis of constant emission is true.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f11.ps} \end{figure}$ Figure 11: Our emission measure distributions (solid for observation taken in 2000 and dashed for observation taken in 2001) and EUVE emission measure distribution (dotted) obtained by Dupree et al. (2003).
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{3414f12.ps} \end{figure}$ Figure 12: Distribution of loops vs. their maximum temperature $T_{\rm p}$ .
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In the text

$\begin{figure} \par\includegraphics[width=16.5cm,clip]{3414f13.ps} \end{figure}$ Figure 13: Coronal plasma pressure vs. temperature for the two observations. The pressures are obtained by the density and temperature values evaluated from the analysis of He-like triplets. Filled diamonds and upper limits indicate the values determined by our analysis of O VII, Ne IX, Mg XI and Si XIII triplet, while open diamonds indicate pressures obtained by the C V and N VI analysis made by Ness et al. (2001).
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In the text

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{3414fa1.ps} \end{figure}$ Figure A.1: LETGS spectrum of Capella (observation taken in 2000, positive and negative orders added) in the region $10{-}12~{\rm \AA}$ .

In the text

$\begin{figure} \par\includegraphics[width=15.7cm,clip]{3414f1.ps} \end{figure}$	Figure 1: LETGS smoothed spectrum (positive and negative orders added) of Capella, with bin size of $0.0125~{\rm \AA}$ , collected on March 8, 2000, split into three parts. Note the different scales in each panel. The labels identify some of the strongest lines.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f2.ps} \end{figure}$	Figure 2: Emission measure distributions calculated with the MCMC method by Kashyap & Drake (1998) for the observation made on March 2000 (solid line) and for the observation made on February 2001 (dotted line). Note that we can provide error bars only for the bins ranging from $\log T=6.2$ to $\log T=7.3$ .
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f3.ps} \end{figure}$	Figure 3: Comparison between observed and predicted line fluxes vs. $T_{{\rm max}}$ (upper panel) and vs. chemical elements and, for iron, ionization stage (lower panel). Filled symbols indicate the lines included in the emission measure reconstruction, open symbols indicate those not included, and triangles indicate the long wavelength lines ( $\lambda >80~{\rm \AA}$ ).
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$\begin{figure} \par\includegraphics[width=15.6cm,clip]{3414f4.ps} \end{figure}$	Figure 4: Comparison between LETGS spectrum of Capella (with error bars), collected on March 8, 2000, and the predicted spectrum (thick line) derived from the reconstructed emission measure distribution.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f6.ps} \end{figure}$	Figure 6: Derived abundances, in solar units (Grevesse et al. 1992), vs. first ionization potential. Filled diamonds are abundances derived from the observation taken on March 2000, open diamonds the ones derived from the observation taken on February 2001.
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$\begin{figure} \par\includegraphics[width=16.5cm,clip]{3414f7.ps} \end{figure}$	Figure 7: Observed and best-fit multi-component model spectrum for the Si XIII, Mg XI, Ne IX and O VII triplets of the positive order of the observation taken on March 2000. Dotted lines represent individual lines while the horizontal line indicates the continuum.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f8.ps} \end{figure}$	Figure 8: Comparison, in $\sigma$ unit, between observed line fluxes of the two observations.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f9.ps} \end{figure}$	Figure 9: Comparison, in $\sigma$ unit, between total observed line fluxes at each $T_{{\rm max}}$ of the two observations.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3414f11.ps} \end{figure}$	Figure 11: Our emission measure distributions (solid for observation taken in 2000 and dashed for observation taken in 2001) and EUVE emission measure distribution (dotted) obtained by Dupree et al. (2003).
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$\begin{figure} \par\includegraphics[width=8cm,clip]{3414f12.ps} \end{figure}$	Figure 12: Distribution of loops vs. their maximum temperature $T_{\rm p}$ .
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