All Figures

$\begin{figure} \includegraphics[width=12cm,height=10.4cm,clip]{7386f001.ps}\end{figure}$ Figure 1: Field of view (42 $\times$ 28 arcmin²) of the CFHT image. The chips are numbered in increasing order from left to right from chip 1 ( top left) to chip 12 ( bottom right); stars of chip 6 are not plotted since we found it impossible to derive accurate photometry. Dashed and solid lines are the edges of the SPM and Loiano fields, respectively. Variable stars are also plotted: blue dots are pulsating variables, purple dots are irregular and cataclysmic variables, green dots and cyan dots are eclipsing systems (EA/EB-type and EW-type, respectively). Finally, red and yellow dots are rotational and long-period variables, respectively.
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In the text

$\begin{figure} \par\includegraphics[width=7.7cm,clip]{7386f002.ps} \end{figure}$ Figure 2: Grey points: r parameter vs. s parameter for constant light curves. Black dots: parameters derived from our light curves for the variable stars previously detected in our field.
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In the text

$\begin{figure} \par\includegraphics[width=7.7cm,clip]{7386f003.ps}\end{figure}$ Figure 3: Proper-motion vector-point diagram for the inner region of NGC 6791 (from Bedin et al. 2006). The circle (centered on the absolute proper motion of the cluster) represents a safe limit corresponding to 0.5 mas/yr. Triangles represent non-members, points with error bars are the new variables 06289_9, 04803_9 and 09831_9.
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In the text

$\begin{figure} \par\includegraphics[width=6cm,clip]{7386f004.ps}\end{figure}$ Figure 4: Stellar density $\rho$ (number of stars per square arcminute) as a function of the distance from the center. The straight line represents the mean stellar density at distances greater than 10 $^\prime$ .
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In the text

$\begin{figure} \par\mbox{\includegraphics[width=2.6cm,height=2.6cm]{7386f05a.ps}... ...5e.ps}\includegraphics[width=2.6cm,height=2.6cm]{7386f05f.ps} } \par\end{figure}$ Figure 5: Light curves of pulsating variables. V123 and 01497_12 are probably HADS stars, 00311_7 and 00224_10 are SX Phe stars, 03653_3 and 00345_1 are RR Lyr stars.
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In the text

$\begin{figure} \par\includegraphics[width=6.5cm,height=8cm,clip]{7386f006.ps}\end{figure}$ Figure 6: Variable stars showing irregular fluctuations.
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In the text

$\begin{figure} \par\includegraphics[width=6.5cm,height=6.5cm]{7386f07a.ps}\par\includegraphics[width=6.5cm,height=6.5cm]{7386f07b.ps}\end{figure}$ Figure 7: Top: light curves of B8 (CV star) and 06289_9 (candidate CV). Bottom: positions in the two-colour diagram for two irregular stars (V83 and V93), for the cataclysmic variable B8 when in a low state, and for the new variable candidate 06289_9.
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In the text

$\begin{figure} \par\mbox{\includegraphics[width=2.6cm,height=2.6cm]{7386f08a.ps}... ...8h.ps}\includegraphics[width=2.6cm,height=2.6cm]{7386f08i.ps} } \par\end{figure}$ Figure 8: The light curves of the contact binaries that are likely members of NGC 6791. The case of 01434_3 (amplitude much larger than 0.75 mag) is also shown in the last panel.
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In the text

$\begin{figure} \par\includegraphics[width=7.5cm,clip]{7386f009.ps} \end{figure}$ Figure 9: The m-M values calculated for contact binaries by means of the Rucinski (2003) P-L-C relation plotted against the distance from the cluster center. Triangles indicate the stars whose membership has been proposed by M03, the filled circles the stars whose membership has been proposed by us, and the open circles the stars that we suggest do not belong to NGC 6791. The starred point indicates the star 09891_9 which does not belong to the cluster on the basis of the proper motion (B06). The (m-M)_V value for the cluster (solid line) with an error bar of $\pm$ 0.20 mag (dashed lines) is also shown.
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In the text

$\begin{figure} \par\includegraphics[width=6.4cm,clip]{7386f10a.ps}\par\vspace*{2mm} \includegraphics[width=6.4cm,clip]{7386f10b.ps} \end{figure}$ Figure 10: The CMDs for the binary systems belonging to NGC 6791. Filled circles are contact binaries (W UMa stars), triangles are detached or semi-detached systems ( $\beta$ Per or $\beta$ Lyr systems).
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In the text

$\begin{figure} \par\mbox{\includegraphics[width=2.6cm,height=2.6cm]{7386f11a.ps}... ...1k.ps}\includegraphics[width=2.6cm,height=2.6cm]{7386f11l.ps} } \par\end{figure}$ Figure 11: The light curves of short-period detached or semi-detached eclipsing binaries.
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In the text

$\begin{figure} \par\mbox{\includegraphics[width=2.6cm,height=2.6cm]{7386f12a.ps}... ...2e.ps}\includegraphics[width=2.6cm,height=2.6cm]{7386f12f.ps} } \par\end{figure}$ Figure 12: The light curves of a small sample of rotational variables, illustrating the growing importance of the second wave.
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In the text

$\begin{figure} \par\includegraphics[width=5.9cm,clip]{7386f13a.ps}\par\vspace*{2mm} \includegraphics[width=5.9cm,clip]{7386f13b.ps}\end{figure}$ Figure 13: (V-I)-V and (B-V)-V diagrams for NGC 6791. The rotational variables that we suggest may belong to the cluster are indicated with filled circles. Triangles: stars belonging to the cluster according to the Cudworth's membership; starred point: V14, open square: V17 (see text for details about these stars).
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In the text

$\begin{figure} \par\includegraphics[width=5.8cm,clip]{7386f14a.ps} \vspace*{2mm} \includegraphics[width=5.8cm,clip]{7386f14b.ps} \end{figure}$ Figure 14: (B-V)-V and (V-I)-V diagrams for NGC 6791. Filled circles: long-period variables that we suggest belong to the cluster. Filled triangles: long-period variables that belong to the cluster (membership probability higher than 76%.)
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In the text

$\begin{figure} \includegraphics[width=9cm,height=13.95cm,clip]{7386f015.ps}\end{figure}$ Figure 15: Light curve of the suspect "red straggler'' V76 $\equiv$ V85 and the five stars that we suggest may belong to the cluster.
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In the text

$\begin{figure} \par\includegraphics[width=3.3cm,height=3.3cm]{7386a101.ps}\inclu... ...raphics[width=3.3cm,height=3.3cm]{7386a129.ps}\hspace*{1.65cm}} \par\end{figure}$ Figure A.1: Contact variables.

In the text

$\begin{figure} \par\includegraphics[width=3.3cm,height=3.3cm]{7386a201.ps}\inclu... ...udegraphics[width=3.3cm,height=3.3cm]{7386a234.ps}\hspace*{1.65cm}} \end{figure}$ Figure A.2: Rotational variables with a single-wave light curve, in some cases very distorted.

In the text

$\begin{figure} \par\includegraphics[width=3.3cm,height=3.3cm]{7386a301.ps}\inclu... ...ludegraphics[width=3.3cm,height=3.3cm]{7386a333.ps}\hspace*{3.3cm}} \end{figure}$ Figure A.3: Rotational variables with a single-wave light curve, in some cases very distorted.

In the text

$\begin{figure} \par\includegraphics[width=3.3cm,height=3.3cm]{7386a401.ps}\inclu... ...graphics[width=3.3cm,height=3.3cm]{7386a422.ps}\hspace*{5.5cm}} \par\end{figure}$ Figure A.4: Rotational variables with a single-wave (from V51 to 05877_9) and a double-wave light curve.

In the text

$\begin{figure} \par\includegraphics[width=7.7cm,clip]{7386f002.ps} \end{figure}$	Figure 2: Grey points: r parameter vs. s parameter for constant light curves. Black dots: parameters derived from our light curves for the variable stars previously detected in our field.
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$\begin{figure} \par\includegraphics[width=7.7cm,clip]{7386f003.ps}\end{figure}$	Figure 3: Proper-motion vector-point diagram for the inner region of NGC 6791 (from Bedin et al. 2006). The circle (centered on the absolute proper motion of the cluster) represents a safe limit corresponding to 0.5 mas/yr. Triangles represent non-members, points with error bars are the new variables 06289_9, 04803_9 and 09831_9.
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$\begin{figure} \par\includegraphics[width=6cm,clip]{7386f004.ps}\end{figure}$	Figure 4: Stellar density $\rho$ (number of stars per square arcminute) as a function of the distance from the center. The straight line represents the mean stellar density at distances greater than 10 $^\prime$ .
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$\begin{figure} \par\mbox{\includegraphics[width=2.6cm,height=2.6cm]{7386f05a.ps}... ...5e.ps}\includegraphics[width=2.6cm,height=2.6cm]{7386f05f.ps} } \par\end{figure}$	Figure 5: Light curves of pulsating variables. V123 and 01497_12 are probably HADS stars, 00311_7 and 00224_10 are SX Phe stars, 03653_3 and 00345_1 are RR Lyr stars.
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$\begin{figure} \par\includegraphics[width=6.5cm,height=8cm,clip]{7386f006.ps}\end{figure}$	Figure 6: Variable stars showing irregular fluctuations.
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$\begin{figure} \par\includegraphics[width=6.5cm,height=6.5cm]{7386f07a.ps}\par\includegraphics[width=6.5cm,height=6.5cm]{7386f07b.ps}\end{figure}$	Figure 7: Top: light curves of B8 (CV star) and 06289_9 (candidate CV). Bottom: positions in the two-colour diagram for two irregular stars (V83 and V93), for the cataclysmic variable B8 when in a low state, and for the new variable candidate 06289_9.
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$\begin{figure} \par\mbox{\includegraphics[width=2.6cm,height=2.6cm]{7386f08a.ps}... ...8h.ps}\includegraphics[width=2.6cm,height=2.6cm]{7386f08i.ps} } \par\end{figure}$	Figure 8: The light curves of the contact binaries that are likely members of NGC 6791. The case of 01434_3 (amplitude much larger than 0.75 mag) is also shown in the last panel.
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$\begin{figure} \par\includegraphics[width=6.4cm,clip]{7386f10a.ps}\par\vspace*{2mm} \includegraphics[width=6.4cm,clip]{7386f10b.ps} \end{figure}$	Figure 10: The CMDs for the binary systems belonging to NGC 6791. Filled circles are contact binaries (W UMa stars), triangles are detached or semi-detached systems ( $\beta$ Per or $\beta$ Lyr systems).
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$\begin{figure} \par\mbox{\includegraphics[width=2.6cm,height=2.6cm]{7386f11a.ps}... ...1k.ps}\includegraphics[width=2.6cm,height=2.6cm]{7386f11l.ps} } \par\end{figure}$	Figure 11: The light curves of short-period detached or semi-detached eclipsing binaries.
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$\begin{figure} \par\mbox{\includegraphics[width=2.6cm,height=2.6cm]{7386f12a.ps}... ...2e.ps}\includegraphics[width=2.6cm,height=2.6cm]{7386f12f.ps} } \par\end{figure}$	Figure 12: The light curves of a small sample of rotational variables, illustrating the growing importance of the second wave.
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$\begin{figure} \par\includegraphics[width=5.9cm,clip]{7386f13a.ps}\par\vspace*{2mm} \includegraphics[width=5.9cm,clip]{7386f13b.ps}\end{figure}$	Figure 13: (V-I)-V and (B-V)-V diagrams for NGC 6791. The rotational variables that we suggest may belong to the cluster are indicated with filled circles. Triangles: stars belonging to the cluster according to the Cudworth's membership; starred point: V14, open square: V17 (see text for details about these stars).
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$\begin{figure} \par\includegraphics[width=5.8cm,clip]{7386f14a.ps} \vspace*{2mm} \includegraphics[width=5.8cm,clip]{7386f14b.ps} \end{figure}$	Figure 14: (B-V)-V and (V-I)-V diagrams for NGC 6791. Filled circles: long-period variables that we suggest belong to the cluster. Filled triangles: long-period variables that belong to the cluster (membership probability higher than 76%.)
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$\begin{figure} \includegraphics[width=9cm,height=13.95cm,clip]{7386f015.ps}\end{figure}$	Figure 15: Light curve of the suspect "red straggler'' V76 $\equiv$ V85 and the five stars that we suggest may belong to the cluster.
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