All Figures

$\begin{figure} \par\includegraphics[width=13cm,clip]{9017fig1.ps} \end{figure}$ Figure 1: XMM-Newton EPIC raw X-ray (sum of PN, MOS1, MOS2 detectors) and OM U band light curves ( bottom panels), UVES blue and red channel ( upper panels) during the first 30 s of the impulsive flare on CN Leo; all times are in UT seconds relative to May 19, 2006, 23:46:25; the inserts show the same light curves covering 1000 s relative to May 19, 2006, 23:39:40 in logarithmic scale, including some quiescent emission and the full flare light curve; the light curve portions displayed enlarged are gray shaded. The X-ray light curves exclude events recorded in the center of the point response function to avoid pile-up effects; the total X-ray count rate is almost twice as large. The binning of all data is 1 s, except that of the X-ray data in the insert, which is set to 100 s prior to the flare onset and to 10 s afterwards. The OM light curve is dead time corrected; for rates above 500 cts/s these corrections and the lightcurve become unreliable.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.2cm,clip]{9017fig2.ps} \end{figure}$ Figure 2: EPIC pn spectrum of burst between UT 23:46:36 to UT 23:46:44 (black data points) together with model fit assuming a thermal spectrum (blue curve) and a power-law (red curve).
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.2cm,clip]{9017fig3.ps} \end{figure}$ Figure 3: Comparison of burst spectrum between UT 23:46:36 to UT 23:46:44 (black data points) with postburst spectrum (red data points) between UT 23:46:44 to UT 23:47:44; a power-law fit with photon index $\gamma = 2$ is also shown.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{9017fig4.ps} \end{figure}$ Figure 4: VLT/UVES spectrum (between UT 23:30:35 to 23:47:15) covering the wavelength range between 3300-3850 Å. Data points are shown as blue histogram, black body fits with temperatures of 11318 K in red and for 10 000 K and 15 000 K as dashed lines. Balmer line emission is visible at longer wavelengths, but at shorter wavelengths most of the flux resides in continuum.
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In the text

$\begin{figure} \par\includegraphics[width=7.7cm,clip]{9017fig5.ps} \end{figure}$ Figure 5: Calculated run of temperature ( upper panel), density (in units of 10⁹ cm^-3; medium panel), and emission measure weighted cooling function ( bottom panel) for the first 20 s of a coronal explosion. The initial state (a quiescent loop with $T_{\rm max} = 3 \times 10^6$ K) is shown as a dotted line, the evolution at times t = 2 s, 4 s, 8 s, and 10 s, during which heating takes place, is shown as solid lines, that at times t = 13 s, 16 s, and 19 s as long-dashed lines.
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In the text

$\begin{figure} \par\includegraphics[width=5.2cm,clip]{9017fig6.ps} \end{figure}$ Figure 6: XMM-Newton X-ray light curve (in erg/s) overplotted over hydrodynamic model prediction; time is with respect to the modeled start of the energy input. Note the good agreement between data and model although no best fit was performed. Also note that the event at t = 13 s might represent a further soft X-ray burst.
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In the text

$\begin{figure} \par\includegraphics[width=8.5cm,clip]{9017fig7.ps} \end{figure}$ Figure 7: XMM-Newton EPIC light curve (bottom panel) and mean photon energy (top panel) vs. time for the first 100 s around flare onset; all times are relative to May, 19th, 2006, 23:46:20. The mean photon energy has been derived from all photons with registered energies >500 eV; each data point represents the mean energy of 200 photons.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.2cm,clip]{9017fig2.ps} \end{figure}$	Figure 2: EPIC pn spectrum of burst between UT 23:46:36 to UT 23:46:44 (black data points) together with model fit assuming a thermal spectrum (blue curve) and a power-law (red curve).
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$\begin{figure} \par\includegraphics[angle=-90,width=8.2cm,clip]{9017fig3.ps} \end{figure}$	Figure 3: Comparison of burst spectrum between UT 23:46:36 to UT 23:46:44 (black data points) with postburst spectrum (red data points) between UT 23:46:44 to UT 23:47:44; a power-law fit with photon index $\gamma = 2$ is also shown.
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$\begin{figure} \par\includegraphics[width=8cm,clip]{9017fig4.ps} \end{figure}$	Figure 4: VLT/UVES spectrum (between UT 23:30:35 to 23:47:15) covering the wavelength range between 3300-3850 Å. Data points are shown as blue histogram, black body fits with temperatures of 11318 K in red and for 10 000 K and 15 000 K as dashed lines. Balmer line emission is visible at longer wavelengths, but at shorter wavelengths most of the flux resides in continuum.
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$\begin{figure} \par\includegraphics[width=5.2cm,clip]{9017fig6.ps} \end{figure}$	Figure 6: XMM-Newton X-ray light curve (in erg/s) overplotted over hydrodynamic model prediction; time is with respect to the modeled start of the energy input. Note the good agreement between data and model although no best fit was performed. Also note that the event at t = 13 s might represent a further soft X-ray burst.
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$\begin{figure} \par\includegraphics[width=8.5cm,clip]{9017fig7.ps} \end{figure}$	Figure 7: XMM-Newton EPIC light curve (bottom panel) and mean photon energy (top panel) vs. time for the first 100 s around flare onset; all times are relative to May, 19th, 2006, 23:46:20. The mean photon energy has been derived from all photons with registered energies >500 eV; each data point represents the mean energy of 200 photons.
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