Astronomy & Astrophysics

All Figures

$\begin{figure} \par\includegraphics[width=15.6cm,clip]{A0464F1a.ps} \end{figure}$ Figure 1: The considered wavelength range of selected program stars. Some strong absorption lines are identified in the top spectrum. The Ti II emission lines are marked in the spectrum of Ad Leo.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=15.6cm,clip]{A0464F1b.ps}\end{figure}$ Figure 1: continued. For LHS 2034 and LHS 2076 the spectra are shown during flare and during quiescent state. Note that these four spectra and the spectrum of UV Cet are not averaged spectra and therefore some remaining cosmics were replaced manually by a straight line.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=7.8cm,height=5cm,clip]{A0464F2a.ps}\hspace*{4mm} \includegraphics[width=7.8cm,height=5cm,clip]{A0464F2b.ps} \end{figure}$ Figure 2: To the left the light curve of the flux of LHS 2076 on March, 15th, corresponding to a single spectrum. On the x-axis the universal time is given. The flux is in arbitrary units since the photometer is used for engineering purposes. The upper light curve corresponds to the red arm of the spectra, while the lower light curve corresponds to the blue arm and is scaled relative to the red flux for convenience. Two short duration flares can be seen in both the red and the blue arm of the photometer following each other rapidly. To the right the spectrum of LHS 2076 during the flare around 3388 Å showing an broad emission feature at 3387.92 Å.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8cm,height=5.2cm,clip=0]{A0464F3.ps} \end{figure}$ Figure 3: Spectrum of CN Leo with a signal to noise ratio artificially reduced to that of DX Cnc. But despite the low signal to noise ratio clearly the Ti II and Fe XIII lines can be recognized.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=7.9cm,height=5.2cm,clip]{A0464F4.ps} \end{figure}$ Figure 4: The spectrum of UV Cet 3388.1 Å (grey) in comparison to the spectrum of CN Leo (black) broadened artificially to the rotational velocity of UV Cet.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=7.9cm,height=5.4cm,clip]{A0464F5a.ps}\... ...*{3mm} \includegraphics[width=7.9cm,height=5.4cm,clip]{A0464F5b.ps} \end{figure}$ Figure 5: Top panel: logarithm of the line flux (in electrons) of the 3387 Å line plotted versus the logarithm of the line flux of the 3380 Å line for the spectra of the CN Leo time series, LHS 2034, LHS 2076 during the flare, YZ CMi, AD Leo, AT Mic. The straight line marks the ratio of unity. The square marks the flux of LHS 2076 where the line is blended with Fe XIII and the fit cannot disentangle the two lines well. Bottom panel: logarithm of the combined flux of the 3387 Å and the Fe XIII line plotted versus the 3380 Å line. The triangles denote UV Cet with respect to the combined set of emission lines. Clearly AD Leo, AT Mic, YZ CMi and LHS 2034 show no Fe XIII line emission, while the UV Cet line ratios are in the regime of stars with additional Fe XIII flux (note, that the square denoting LHS 2076 has moved above the line of unity).
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.4cm,height=5.3cm,clip]{A0464F6a.ps}\... ...{3mm} \includegraphics[width=8.4cm,height=5.3cm,clip]{A0464F6c.ps} \end{figure}$ Figure 6: The best fit of the 3387 Å line for the stars AD Leo, AT Mic and YZ CMi with the rotational broadened spectra of GJ 229 as background (black line).
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8cm,height=5.1cm,clip]{A0464F7.ps} \end{figure}$ Figure 7: Light curve of the flux of CN Leo on March, 16th, during the second observation block but otherwise like in Fig. 2. Clearly a major flare can be seen in both the red and the blue arm of the photometer.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.1cm,height=5.1cm,clip]{A0464F8a.ps}\... ...phics[width=8.1cm,height=5.1cm,clip]{A0464F8g.ps}\hspace*{4.4cm}} \end{figure}$ Figure 8: Best fit of the Ti II line together with the Fe XIII line in the averaged spectral series. At the top the two spectra taken on March, 13th (left: start time 2.3 UT right: start time 4.2 UT), beneath the two spectra taken on March, 15th (left: start time 3.7 UT, right: start time 6.4 UT), beneath the spectra taken on March, 16th (left: start time 3.9 UT, right: start time 5.9 UT). The single spectrum at the bottom was taken on March, 14th (start time 3.1 UT). The horizontal line in each spectrum indicates the background used for the line fitting.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=7.7cm,height=4.7cm,clip]{A0464F9.ps} \end{figure}$ Figure 9: The spectrum of CN Leo around the Ca XII line. Two Ti II lines are identified; the other faint emission features are unidentified.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=7.5cm,height=4.9cm,clip]{A0464F10.ps} \end{figure}$ Figure 10: Contour plot of the flux ratios between the Ca XII and the Fe XIII line (black) for a set of temperatures and electron densities and for the ratios of the Fe XIV and the Fe XIII line (grey). The inner line represents a ratio of 0.4, the middle line a ratio of 0.5 and the outer line a ratio of 0.6 for Ca XII and for Fe XIV the inner line represents a ratio of 5.0, the middle line a ratio of 5.5 and the outer line a ratio of 6.0. The shaded area denotes the parameter set that is in agreement with the non-detection of Ca XII and Fe XIV.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=15.6cm,clip]{A0464F1a.ps} \end{figure}$	Figure 1: The considered wavelength range of selected program stars. Some strong absorption lines are identified in the top spectrum. The Ti II emission lines are marked in the spectrum of Ad Leo.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=15.6cm,clip]{A0464F1b.ps}\end{figure}$	Figure 1: continued. For LHS 2034 and LHS 2076 the spectra are shown during flare and during quiescent state. Note that these four spectra and the spectrum of UV Cet are not averaged spectra and therefore some remaining cosmics were replaced manually by a straight line.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8cm,height=5.2cm,clip=0]{A0464F3.ps} \end{figure}$	Figure 3: Spectrum of CN Leo with a signal to noise ratio artificially reduced to that of DX Cnc. But despite the low signal to noise ratio clearly the Ti II and Fe XIII lines can be recognized.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=7.9cm,height=5.2cm,clip]{A0464F4.ps} \end{figure}$	Figure 4: The spectrum of UV Cet 3388.1 Å (grey) in comparison to the spectrum of CN Leo (black) broadened artificially to the rotational velocity of UV Cet.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.4cm,height=5.3cm,clip]{A0464F6a.ps}\... ...{3mm} \includegraphics[width=8.4cm,height=5.3cm,clip]{A0464F6c.ps} \end{figure}$	Figure 6: The best fit of the 3387 Å line for the stars AD Leo, AT Mic and YZ CMi with the rotational broadened spectra of GJ 229 as background (black line).
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8cm,height=5.1cm,clip]{A0464F7.ps} \end{figure}$	Figure 7: Light curve of the flux of CN Leo on March, 16th, during the second observation block but otherwise like in Fig. 2. Clearly a major flare can be seen in both the red and the blue arm of the photometer.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=7.7cm,height=4.7cm,clip]{A0464F9.ps} \end{figure}$	Figure 9: The spectrum of CN Leo around the Ca XII line. Two Ti II lines are identified; the other faint emission features are unidentified.
Open with DEXTER